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>> Last Updated: 01/23/2012 11:54 AM Central Time <<
5. Performance, Tuning (Back to Topics)
Index to Performance & Tuning: (Back to Topics)
Making More Horse Power (updated 9/23/06) BACK TO INDEX
Making horsepower and torque is all about moving air - intake and exhaust. To get the most out of your V*Star 1100 you will have to address both the front and back end of the air-fuel cycle.
This means you will need to:
1.) increase the air flow on the intake side (better air cleaners, removal of restrictions, etc)
2.) increase the flow on the exhaust side (better pipes - slip-on, full 2 into 2, full 2 into 1 and performance pipes)
3.) change the jetting to match and take advantage of your new, freer flowing system.
What follows is the current thinking about the different ways to accomplish these tasks.
This section will focus mainly on the intake and carburetor portion of the process, and you can refer to the exhaust section for more info on how to handle that end of the process.
For more general info on the process - here is a link to an excellent Article, provided to the forum by hoghead63:
http://motorcycleinfo.calsci.com/HP2.html
Sir Isaac Newton on Power, Torque & Acceleration
(Engines Mods & Performance Modeling) -- An Excellent Article (pdf file) (added 01/23/13)
Discussion: (updated 07/11/09)
Significant testing and Dynoing by the early tuners and users of pod kits with various exhaust types has resulted in a ton of info -- and you can rest assured that if you follow the pod installation and jetting instructions for your kind of exhaust -- the results will be fairly close to what is portrayed below - for your modifications status!, There is no real need for you to spend your $$ on a Dyno run, unless you are getting unexpected results or problems.
If you decide on the Dyno route, the major item for tuning your bike after making fuel / air changes (jets, pods, etc) is the AFR - Air Fuel Ratio. This item is one of the 3 things you want to get recorded when you have your ride Dynoed, the other ones being Horsepower and Torque.
"Perfect" AFR is 14.7 parts of air to 1 part fuel = AFR = 14.7. Comment: "As it is impossible for any carb to deliver perfect air/fuel ratios, you always try to be a little richer across the range - if you can. Running a LITTLE rich also improves drivability. Too rich and the engine chokes on the fuel and can't burn it all properly, and power drops off." (raymajor)
If you look at Dyno sheets, you will note that maximum HP is produced at Wide Open Throttle and AFR is in the 12.1 to 12.5 range.
NOTE: all of the numbers below were derived from dynometer sheets taken from Dyno brand dynometers.
NOTE: HP from dyno machines is sensitive to many factors: altitude, humidity, temperature and to the settings made by the dyno operator (the operator can skew the numbers by 3-4 HP) -- all these factors make comparison very difficult. Dyno dynos are considered to be quite accurate - but, given these variables, the only way to truly compare is to get reading with the Dyno smoothing factor set to a 5 - which adjusts real conditions to an "ideal" state for all the variables - making comparison easy, but not giving you the "real" HP under your "real" conditions.
THE TABLE BELOW IS OUR CURRENT BEST ESTIMATE OF THE HP TO BE EXPECTED FROM THE CONFIGURATIONS NOTED.
IT IS NOT A CASE OF "smoke & mirrors" to get the numbers, but IS a case of "too many variables (above)" for us to be dead accurate. Sorry, but you will have to deal with our best estimates - not perfection, but the best we have to offer.
YOUR RESULTS MAY VARY!! If you get a wide variation, then post to the forum and see what the experts say.
DO NOT COMPLAIN TO "MANAGEMENT" IF YOUR RESULTS ARE WITHIN PLUS/MINUS 5% OF THESE NUMBERS
Given the potential for variability, a forum member has said we might be better off making the table look like:
Modification Status Approx. HP Pods and 2-2 pipe Low 60's
Pods and 2-1 pipe Mid 60's Cams, Pods and pipes Low to Mid 70's
This would surely make my life easier - but would rob you of information,
so here is the "real deal", courtesy of lotsa members, and the analysis of cruzmystar (THANKS!)
Modification Status (updated 07/11/09) Approx. HP Stock Bike - Untouched 48-51 Stock Intake, Full 2-2 Exhaust 55-58 Stock Intake, "Performance" Exhaust (see list below) 57-60 Pod Kit, Drilled Stock Exhaust 55-58 Pod Kit, Aftermarket Slip-on Exhaust 56-60 Pod Kit, Full Replacement Exhaust (Not Performance) 61-65 Pod Kit, "Performance" Exhaust (see list below) 64-67 POD Kit, Full Replacement Exhaust (Not Performance), Midrange Cams 71-73 Pod Kit, "Performance" 2-to-1 Exhaust, Midrange Cams 73-76 OTHER, SINGLE CASE CONFIGURATIONS: KJS 1 Flat Side Carb, Full Replacement 2-2 Exhaust 68 Turbo - Nick's Mods - 19.5psi boost 110 Octane Fuel 112
Note:
Current list of "Performance" pipes includes: Cobra HP 2-1, PCS Monster Pro 2-2 (despite looks), Roadhouse classic 2-1, Pro-Race Pipe by S&S Custom Cycle 2-1 and . . . . (List also in Jetting 101 section - note to myself)The Cobra 2 into 1 pipes, either the trumpet or the straight ended ones, have been turning out the best HP of all the "performance" 2-1 pipes - and you should expect to get an added 2-4 HP from them with the baffle plate drilled.Note:
Note: Shane, S&S Customs, is finding the Cobra Speedsters 2-2, with their cross-over "port" are delivering similar HP to the Cobra 2 into 1's - maybe 1 -2 HP less - so if you like 2 into 2 look - they sound like a real good bet!
Note: Any sort of intake kit that still retains the factory air-box (Hypercharger, High-V, BAK, Speedstar, etc.) will show a couple HP less than POD kit numbers until you start dealing with aftermarket cams then it will taper off more significantly than the numbers in the chart. POD kits are easier to tune, and tune well!
More on Hyper Charger, the Big Air Kit and the Speedstar intake
Missing from this chart and the discussion below is what to expect from the other air intake mods, such as the Hyper charger, the Big Air Kit and the Speedstar intake, as well as the DIY Air in take mod - all discussed below. the lack of data is the hindrance to including those mods in this table. Most folks who make mods for power are focused on the various POD setup, and therefore we have a lot of data on those application - in combination with lots of exhaust system.
We know a good tuner can get comparable HP from the bike with the Hypercharger and / or the BAK
- here's a quote from our favorite "tuner":
"I did a customers stock 1100,... Cobra high-boy shot guns with a hyper-charger and Dyna 3000 it pulled 63 HP at the wheel. It also pulled perfect from idle to top end and I have the Dyno sheets to show it, I'll post the sheet for you to see. I've seen the same results with the BAK... I've also never seen anyone with pods and pipes break 65hp,...Maybe on a real generous Dyno but, the average with pods and pipes is 60 just like all other kits. With that being said, I do think that if you have not added a air kit already the pods are the best way to go. They are easier to tune, perform well and can stay even with internal mods.. Shane, Pres. SS Custom Cycle Inc.
If you have done the other type of intake mods and have data (jetting, Dyno results for HP/TQ, make a post on the forum - sparks debate, gets others to chime in and will eventually get the data in here.
Note: See section on Cams for details on what cams do for you relative to other cams.
Another view: Vstar_in_NH:
-- Stock V*Stars are 48-51hp,
-- Air kit with 2-2 pipes will get you about 7-10 hp.
-- Use a 2-1 pipe and an ignition box you'll see 12-15hp.
-- Unless they have it dynoed before and after showing the AFR and TQ/HP it's just a guess
-- every bike is different within a few ponys.
-- I just dynoed mine with Bub Big Willies w/ 1.5in baffles, 420 cams, dual stock carbs, Dyna 2k ignition on curve 7.
I got 62hp and 70TQ SAE corrected, slightly rich on mix. So I'd say 2 more ponys are there.. maybe.
-- If I go to a 2-1 pipe I'd get more.
-- I got 68hp and 92TQ with the same setup only I used a KJS intake and a flat slide carb instead of the stock carb setup.
-- We are working on an EFI system that so far has put us at 68HP and 98TQ. The pipe is the biggest hold back.
-- Bottom line is an air kit will get you about 7-10 ponys, IF setup correctly. Is it worth it? .... Yes!
Dyno Sheets WANTED!!! - with Bike Setup Details (if you have them -- send them in!):
Exhaust Mods BACK TO INDEX
Discussion:
Several different exhaust options are used as variables in the performance tables listed in the next sections. For additional information on exhaust pipe options, modifications, etc. see the Chapter on Exhaust.
As noted above, the maximum benefit in performance improvement is a result of changing both the intake and exhaust setup. If you change to a freer flowing exhaust system, you will notice popping on deceleration, a 'fault" that can be removed by Plugging or Removing the AIS System - Information here.
Air Intake Modifications (updated 8/05/06) BACK TO INDEX
Performance Mods Discussion: -- One Guy's Opinion (More Follow) - SilverBack BACK TO INDEX
These bike are capable of much higher output of torque and horsepower than the manufacturer provides stock. The addition of improved air flow into the bike and the addition of a free flowing exhaust system can really boost performance. (See other discussion below)
Air intake mods run the gamut from: changing out the stock filter for more free flowing filters like the K&N products: to DIY increases to air flow via opening the stock flow restrictions: to Hyper chargers BigAirKits and Speedstar Cover: to POD kits: to single manifold - single carb mods. Most will require jetting changes to allow improved fuel flow to accommodate the increased air flow. And all require better, more free flowing pipes to make the most of the changes.
All of the mods are within the scope of any rider to install themselves - especially with the help and guidance available form: the excellent directions the vendors supply: added information available here: AND the help available from the members of the forum.
Switching to a K&N filter will give you some improvement, but still uses 100% of the restrictive air passages in stock mode. Doing the DIY mod along with the K&N filter, removes the smallest restriction but still leaves the other ones in place (you enlarge the hole that provides the initial intake, but leave the stock tube from the air cleaner to the stock air box under the seat - still restrictive!). You do get some HP improvements from these changes, and jetting may be required.
The same is true of the Hyper Chargers, BAKs and Speedstar Cover with K&N filters, all of which do use the same outlet to the air box, and also moves the air source from between the cylinders to outside the right side of the stock air filter location. Some argue that the scoop nature of the hyper chargers forces air into the bike. Lacking measurements, etc, I am some what skeptical of this argument, given that the bike is sucking air in to beat the band and there does not really seem to be a lot of air flow in the area of the hyper charger scoop. (This is another one of those "on faith" things - so don't yell at me unless you have repeatable tests, proof, etc). See Daddo - Larry Marino's comments below on the Hyper Charger. You do get some HP changes and jetting is required.
Also, several of the "in the know" folks say that you can get as much HP (and maybe a little more torque) from a properly tuned bike with good, full system pipes and the Hyper charger. See comments above. ((Hyper chargers look really cool and lots of folks who have switched to PODs leave the hyper charger in place for looks - and even hook a vacuum line up so the flappers flap.))
Pod Kits are the most popular of the air intake mods, giving the most
improved power for the dollars & time invested. They also are the best
first stage of improvement for those on their way to adding cams and other
performance mods. They are also the easiest air mods to tune for
maximum performance, part due to their prevalence and the amount of
performance and tuning information and help available.
POD kits replace the very restrictive stock intake system from the air cleaner inward through and including the air box under the tank - with individual pod filters (hence the name) perched directly on top of the carbs under the fuel tank. The kits include the jetting parts needed to handle the increased air flow, with instructions on jetting needed for stock, slip-on and full exhaust systems. YES, there are improvements for all types of exhaust systems, even stock. But, the maximum power benefit comes from opening up both ends - increasing air flow and unrestricting the exhaust.
Metric Magic (Tim Bondurant) has introduced a pod system with elbows and attachments and filters that are mounted out from under the tank - one on each side. Going by the name Dragon's Breath, this pod setup looks real cool, provides good leg clearance, and makes it a snap to clean and service the K&N filters provided
The maximum improvement comes from doing the pod kit and full exhaust at the same time, and that also means you will only have to mess with the jetting once. But doing the jetting a second time is really no big deal, so if cash flow precludes doing both together, do them in stages.
When you move on to the single manifold - single carb solution, you get vastly different area where performance is improved - improvement over a broader range of rpm's, but is concentrated in the lower rpm's. Ton's of torque and lots of get up and go on the bottom end. (See the discussion below from Vstar-In-NH (Jack Rosa) who has done it all ways.
Jack is also working now on a fuel injection alternative - which should really prove interesting as it matures. (Don't bug me on this)
More Discussion - Hyper Chargers (Etc) Work, But! - Daddo (DaddoCFL): (updated 7/1/06)
Well, Hyperchargers
absolutely do work, albeit not in the way that you might need or want.
They can be effectively tuned for a specific cruising speed to give you
impressive acceleration in a throttle roll-on. Unfortunately that comes with
just so-so performance the rest of the time at lower speeds where you will
actually be over-jetted for the airflow.
They are hellishly hard to tune the carburetors to, as the change in air
pressure in the intake system is radically different at 30mph and 65 mph. At
idle and low speeds there is a measurable vacuum in the inlet air stream
(that is how we balance our carburetors).
At speed there is an overpressure condition that is higher then the ambient
air pressure where you are. At speed, it performs like a supercharger.
First of all let's stop to consider the
fact that it is a RAM AIR INDUCTION device. If you try to tune the thing on
a Dyno, you will get miserable results, unless you Dyno is in a wind tunnel.
Short of that you would need to in some way provide accelerated airflow to
the Hypercharger inlet, at a velocity that would match the speed you want to
tune it for.
The fact is, you really can’t use this method as static Dyno tests will only
give you a fairly clear picture of the HP and Torque of a bike that is not
going anywhere, but just spinning the hell out of it's drive train with an
artificial load on the drive wheel.
What does that mean at 40, 60, or 80 MPH??? Well it does not really tell you
anything. That is perhaps why the Dyno run will just indicate about a 1 HP
increase across the band. Just about the same as you get with a larger and
less restrictive air filter. The manufacturers that offer this equipment
really just give your their best estimate of the correct rejetting that will
make the boy run well at the HP peak of your power band (most of the time).
What about your Hypercharger installation working too well? On some
installations, on some bikes, the inlet actually takes in too much air. When
that occurs, the carburetor venturi tends to pressurize, and in effect,
restricts or stops the flow of fuel. The solution, worked out by a group of
Vulcan riders (see, they are good guys too), was to also pressurize the
carburetor float bowl as well. They had accomplished this by running an
additional air hose(s) from the Air ram to the carburetor float bowls. You
can find a reference to this on (and I hope that the link is still there):
www.sa750.com/hypercharger/hypercharger2.htm.
I would expect that this same principle also applies to most Big Air Kits,
How many of them have been tested in an environment that duplicates the
airflow of a bike moving at speed? A volume of air moving at speed past a
stationary object usually results in a big-time pressure drop. While the BAK
filter is in an area of substantial turbulence, there still remains a
pressure wave on the leading face, and a major negative pressure on the
trailing side. Does that result in a positive or negative partial pressure
inside the air box?? Well I don't know, and I bet most of the manufacturers
don't know either. It MUST be tested at speed with internal pressure sensors
inside the filter housing and at the carburetor inlet.
I would expect that Kuryakyn has now addressed this issue and resolved it.
As the Hypercharger has been available for HD applications for some time now
you will find a lot of data and testimonials on the HD specific
bulletin boards. Good I wish you well with whatever system you choose.
Even More Discussion - KJS Gives the Most - "Vstar_in_NH": (updated 1/10/06)
No hype here.. Well, Best bang
for the buck... Hmmm, I've done most of the common performance mods, air
kit, KJS manifold, Cams, Stock modded pipes, slip-ons, Cobra low boys, Bub
Big Willys, Dyna ignition and currently working on an EFI. I've dynoed all
of them and Have solid real data as well as riding experience with these.
Here is what I have found to be the best bang for the buck.
1) KJS manifold, Mikuni HS 40 carb, Bub pipes and a Dyna ignition. MEGA
torque and good HP, super easy to work on and overall the most fun.
2) KJS manifold, Mikuni HS 40 carb, Bub pipes, S&S 420 cams and a Dyna
ignition. good torque and good HP but extended way up in the RPMs.
3) Stock carbs, Pod air kit (Max Air, Cycle Foray, etc same performance), S&S
420 cams, Bub Big Willys and Dyna ignition. Fair torque, good HP but the
highway and high rpm the motor likes to live there.
4) Stock carbs, Pod air kit (Max Air, Cycle Foray, etc), Bub Big Willys and
Dyna ignition. More breathing better revving then stock.
Any 2-1 pipe will get me 5-7 more hp, but I like the 2-2 sound.
Doing the air kit is easy, Even
the most popular installed still has people looking at the BEAK instructions.
It's "friggin" easy. Build it yourself, save $60-80 bucks. We can get you
setup on the forum here. Here is what you need.
http://vstar1100.froggbox.com/airkit.htm
Or you can make your Vstar sound and perform like a raging beast by using a
KJS kit, which by it's self even with stock pipes and ignition will yield
over 78lbs of torque! Check out my video on the sound and the Dyno runs I
have posted on my site.
Here is the link to KJS --
http://www.kjsmotorcycleworks.com
Here is the link to my site. --
http://vstar1100.froggbox.com
Come over to the KJS forum and check out all the data from the guys. --
http://forums.delphiforums.com/vstarclinic/start
I have a lot of info posted on my site on the true performance of these mods
measured on the same bike on the same dyno. Don't get hyped, keep a level
head and choose. Make your plan on mods and go for it. Beware of the cult of
the air kit kind of thing, you'll hear a lot of "I got 100hp cuz they tossed
and air filter on". Take your time deciding and most of all focus on the way
you plan to ride. Good luck, We're here for ya!
Summary:
The question you need to consider is how do you plan to ride?
Are you into wringing it out a lot? Tucking on the tank and going hell bent for leather?
Or are you going to be spending more time cruising?
Riding 2 up, jumping off the line light to light and just ripping around?
-- Mild cams are good all around performance, but payoff when you are pulling above 4200-4500 rpm,
-- Stock cams with the KJS manifold will give you ripping power from 1800-4800 rpm, but fall off after 5200 rpm. On the highway the KJS was much better then stock, but when I added the cams over 95mph in 5th gear it pulled better with cams.
-- Pod's with cams felt basically like stock except the power does not fall off until you hit 6200 rpm then it falls off.
If you look at the Dyno charts you can see the curves. Smooth arcs are long building power, steep curves are hold on to the handle bars or you'll fall of power. Each one has it's use. The key is "Power Placement" and "throttle management" Put the power where it will do the most good for the majority of your riding. If you take a 100 mile trip, of the 100 miles how many miles will you be WOT (Wide open Throttle) 5-10? Think about it.. Peak HP #'s are not everything, power placement is key. If you are going to run the 1/4 mile every weekend then Pods, cams and a 2-1 are what you're looking for. But if the majority of the time you'll be riding to work around the hills, dusting off your bro light to light then torque is more of what your looking for.. It's not that you can't use either to race, It's just they deliver different power and therefore will require you to adapt your riding style to meet the need.
DIY Air Intake Mods BACK TO INDEX
DIY Hy-FLOW Factory Air Cleaner - Tony Anzalone
This mod increases the air flow from the "dog bowl" stock air cleaner by: significantly increasing the air intake by enlarging the inlet hole size in the rear of the assembly and by modifying and installing a K&N filter - The mod does retain the stock air-box, and does require jetting changes for some exhaust systems.
Hyper Charger & BAK (Big Air Kit) & Speedstar Cover (updated 09/13/07) BACK TO INDEX
Discussion: See general discussion above.
NOTE:
We are trying to accumulate jetting information to build up the base of info on the use of these devices.
We invite folks with any of these setups, to communicate (via email to Silverback or via post on the forum) your exact set-up: which device, what pipes, jetting, needle and PMS settings, and any other info you feel might be helpful. If you are not sure - check the documentation that came with the package and/or check with whomever installed the device.
If you have the installation instructions - please contact Silverback - so we can work out the best way to get an electronic copy to put on file.
Jetting (updated 01/17/09)
Hypercharger - From Kuryakyn:
With stock exhaust or Cobra Slip-On Mufflers
• 1.2 Pilot Air Bleeds in both carbs
• One .020 shim added to raise each needle
• 122.5 Main Jet in the front cylinder’s carb
• 120 Main Jet in the rear cylinder’s carb
• Pilot Mixture Screw (PMS) 2 turns out from lightly bottomedWith Vance & Hines, Samson, or open “Drag” pipes
• 1.2 Pilot Air Bleeds in both carbs
• One .020 shim added to raise each needle
• 125 Main Jet in the front cylinder’s carb
• 122.5 Main Jet in the rear cylinder’s carb
• Pilot Mixture Screw (PMS) 2 turns out from lightly bottomedhttp://www.kuryakyn.com/documents/installation/9409-25MC-0308.pdf
BAK - Input from Squirrel aka Rob Lewis
I would like to share what I learned installing a Barons Big Air Kit on my '07 1100 Classic. Hopefully this can give you a start for the BAK's. Also many people go with the pod installation and modify the carbs for this, but my bike is still under warranty and I didn't want to chop up my carbs and void the warranty. This is the reason for the BAK.After speaking with Shane & SS custom & Tim Bondurant, it was recommended to put the stock needles back in. Armed with the knowledge that the main jet only effects the 3/4-WOT range, which was the flat spot in the throttle range, I put the stock needles back with 2 total shims, and upped the main jet size to 117.5 front & 115 rear. The idle circuit seemed rich so I closed up the PMS to 2.75 turns. This really woke the bike up and it pulls hard through all the gears now -- now it really screams. I can cruise 65-70mph now in 4th, where previously, it was hard to keep 70mp in 5th.
Sources:
Pod Kits: (updated 03/16/11) BACK TO INDEX
Note: 2006 & Later Owners - there are special considerations required for these bikes and their carb design - which has unique impact (s) on tuning - see discussion below in the 2006 / Catalytic Converter Bike Needs Section. This section covers the need to replace or modify the Main Jet Holder to eliminate fule flow restrictions.
DIY - Pod Kit (updated 05/16/08) BACK TO INDEX
You can build one yourself for around $68.00 (old price, now $80 to $100).
Here's how to do it.. (Courtesy of Jack Vstar_In_NH )
(2) K&N RU-0600 filters
(2) 145 (or other sized) main jets for use depending on which aftermarket exhaust
(2) 22.5 pilot jets
(2) 0.020" thick M3 shims/ washers on each needle (Get from Radio
Shack (part # 64-3022) or from RC car retailer/hobby shop)
Note: use 2.5-3 turns on the stock Pilot screw
(8) M4-.7 pitch 8mm long (10mm long works also) socket head screws for the carb bowls
because you will
likely damage the stock ones when removing them.
(8) M4 lock washers (Not really required - they hold fine without
the washers - or reuse the stock ones)
(1) Breather filter UNI filter UP-123
Also: Make your own
crank case vent collection bottle -
http://www.dumpit.org/reaperjr/vent.htm
All of the parts mentioned above can be had at Phat Performance Parts...
http://www.phatperformanceparts.com/merchant2/merchant.mvc
Download the jetting article here (new link) if you have never jetted a carb before (courtesy of Steve at CycleForay - site off line now).
Also:
"The issue of attaching the
pods to the rubber intake boots was addressed by a few of the forum
regulars when I asked the question a couple of weeks ago. To summarize,
using K&N RU-0600 air filters (which seem to be the most often suggested
pods for this project), one finds that these filters slip right into the
rubber intake boots and can be clamped down as easy as that. However,
somewhere out there is a pot-hole that's waiting to dislodge the pod
from the rubber boot and wreck havoc before I have a clue as to what's
happening. So I went the safe route and cut a piece of chrome pipe for
each pod to slip between the filter and the boot to give the clamp
something more to hang onto (than rubber to rubber). Got two pieces of
pipe at a muffler shop for $5. They are 2 1/4" OD and about 5/8" in
length. (That was AFTER trying to cut the pieces myself with a hacksaw -
which only served to remind me how imperfect hacksaw cutting is!)
Oh
yeah, and my thanks to Ray Major for warning me (ahead of time) that I
would need to swap the rubber intake boots in order for the K&N filters
to fit under the tank (without slightly smashing the rear filter)."
from JCASSIO
Must Read Thread on DIY Pods: http://forums.delphiforums.com/yamaha1100/messages?msg=17739.1
Excellent thread on the DIY Pods: http://forums.delphiforums.com/yamaha1100/messages?msg=17428.1
Thread on "Cheap Pod Filters" - http://forums.delphiforums.com/yamaha1100/messages?msg=33326.1
Pilot Thumbscrews: BACK TO INDEX
Don't forget to order your pilot thumbscrews if you don't want to use the stock ones. These Mikuni parts will fit our carbs and allow the pilot to be adjusted without the use of tools... look for these Mikuni parts.
NOTE: these are the same as the MaxAir MaxMix screws - set them
accordingly (they are NOT the same as stock PMS screws!)
(2) O-Ring, Fuel Screw N133.037
(2) Washer, Fuel Screw VM12/33
(2) Spring, Fuel Screw N133.206
(2) Screw, Pilot Fuel 604-26003
Contact Bernie at Fox Distributing to order... 630-513-9700 (Illinois)
An Alternate Way:
Biker Bill (wwbill_mi) :
I did the DIY air kit, and used Emgo pod filters. They fit with no
problems and are cheaper than the K&N and UNI filters. see them here
http://www.bikebandit.com/partsbandit/product~pf_id~3201529~dept_id~1183583.asp
-- they are only $7.00 each.
I also used a muffler adapter that fits a 2.5 id to 2 id to make they air
filter adapter, I just cut it down to a 1/2 inch longon each side.
http://store.summitracing.com/partdetail.asp?autofilter=1&part=WLK%2D41958&N=700+%2D120454+115&autoview=sku
Larry Rymal's Another Way - Without the POD Noise
Larry_Rymal (Rymal1)
Retained the bottom half of the stock air box, and then fitted filters on top of that - still fits under the tank - and the noise is gone!!
Here's the link to the thread with explanation and pictures - Nice Job Larry!!!
First, read this:
http://forums.delphiforums.com/yamaha1100/messages?msg=21159.20
Then read this:
http://forums.delphiforums.com/yamaha1100/messages?msg=21159.37
And here is a variation - using an existing MaxAir Kit - and quieting it down Thanks to howsonIII:
http://forums.delphiforums.com/yamaha1100/messages?msg=51669.1
Another Low Noise Pod Setup - navistar71 (ziggy6050)
I installed 1/4 in thick plastic mud-flap material cut to go over frame rails with 4 inch holes drilled through it for the POD air filters. I bolted it in place where the original air box bolted in the rear and through frame in the front. This took care of most of the pod noise.
And Even Another Quiet Pod Way - VStarStruC -
http://forums.delphiforums.com/yamaha1100/messages?msg=30131.1
Under Tank Pod Kits - Vendors/Manufacturers (updated 05/22/08) BACK TO INDEX
www.metric-magic.com Dragon's Breath
As noted earlier, this is a unique pod kit as it locates the PODS (K&N Chrome capped filters) out from under the tank, by your knees on both sides of the bike
The following vendors provide the 'classic" under the tank solution:
www.sscustomcycle.com/products/engine/v-star1100.shtml (look for the chubby)
www.metric-magic.com (as well as Dragons' Breath)
www.factorypro.com/Prod_Pages/prody41.html
Note: many forum members have complained about poor customer service from this vendor,
and the forum experts have identified significant potential for engine damage if this product
is installed as recommended by the vendor on bikes with catalytic convertors .
It is strongly suggested you post to the forum if you are intending to buy this product for newer bikes.
www.cycleforay.com (look for the BEAK) - No Longer Available
POD Type (K&N vs Foam) Comparison - CycleForay - Steve
Jetting Instructions - ABC's (updated 08/11/09)
Note: Contains detailed step by step instructions, starting with tank removal and then all the steps thru completion.
Excellent Jetting Article (DIY or Supplement Mfgr Instructions) -- Courtesy of Steve formerly at www.CycleForay.com
NOTE: When removing the carbs from the bike (per above instructions) remember to loosen the hold-on clamps all the way - repeat - all the way (but not out of the nut)! This will make it much easier to get the carbs back into the bike. Also, use a little spit in the carb flanges that go into the engine "holes" - is a good temporary lube and will dry out - so the carbs will not pop out later, which can happen if you use a true lube (oil, grease, etc)
Some supplemental pictures - courtesy of drenfro22:
A. B. C. D.
A. Late models - 4 Connectors to separate - Also shows breather hose (was connected to air-box)
B. Boot connection to cylinder
C. Boot connection to air-box (rear cycl.)
D. Boot connection to air-box (front cycl.)
Exposed POD Kits (updated 1/30/06) BACK TO INDEX
Metric Magic (Tim Bondurant) has designed and now implemented an alternative to the 'classic" under the tank pod kit.
His product, Dragon's Breath, is described above and in detail on his site, referenced above.
This section here is to trace the idea back to Joe Conaway, who had been experimenting with an alternative arrangement, and more, to the normal pods-under-the-tank air intake mod. He has used 90 degree elbows, mounted the pods/filters out board of the carbs, one on each side, and applied cool covers for the filters.
Some comments from Joe:
Just figured I'd share the air kit I made up using 400 series Ramflo filters. One on each side both are functional. Parts can be had for around $85, but there is a bit of work to get them on there. I welded a 2 1/8 exhaust ring to the back of each filter to attach to the elbows I used. The filters can be bought with blank backing plates so a hole would also need to be made.
The filters I used had two holes so one was widen and used and the other covered. To connect each filter to the respective carb I used PVC 90* 2" elbows "trimmed" to fit , and one small L bracket off the cam chain tensioner mounting bolt to support the filters. Anyway there's a bit more to it, but this will give the general idea of what was done.
"The hardest part was getting the filter centered. I have aftermarket Keihin carbs which are a bit wider from open end to open end than the stock carbs. You need to use the 400cfm filter as well. I used a 2" PVC 90* elbow cut down, I welded an exhaust ring to the back of the ramflos. Then I just used a simple L bracket off one of the tensioner mount bolts the one side is the tensioner hole cover bolt, but same thing). Just took a little time fitting it and it work great. Jetting is the same as pod filters.
Anyone that wants to make these can be my guest. LOL. I made one and that's it. And Tim took it from there.
See Joe's discussion thread here.
Pod Kits - Installation & Hints (updated 06/29/09) BACK TO INDEX
Make your own Oil breather collection bottle -http://www.dumpit.org/reaperjr/vent.htm
Note: Our own TimB says that it is dangerous to use steel wool - given the off chance that a piece might get sucked back into the engine and do damage. I would suggest that a plastic mesh (scrubbie) be used instead of steel wool - all you are looking for is a lot of surface for the misty oil vapor to condense upon.
Filter Pods - Foam vs K&N) --You Make The Call -- Steve Schneider, CycleForay
Same subject, another view -- DaddoCFL
Functionally I don’t know
that any of the options are better then the others. I kind of prefer the
type using K&N filters.
The K&N style is a bit more expensive than Foam construction filters but
having used both types for 40+ years, I think that they will outlast the
(a bit) less sturdy Foam elements (albeit, the foam is relatively cheap
to change). Since both types are well protected under the tank, this is
almost an insignificant issue.
Cleaning either type is very easy as the filter oil is water soluble and
just washes off with a mild degreaser.
Both types are equally good at getting dirty (lol). But aren’t you glad
that they stopped the dirt and road gool from being sucked through the
carbs? Cleaning frequency is a function of engine hours and riding
environment. There is no single answer for you. When there is a visible
coating of crud on the filters, being slightly anal retentive about such
things, I clean them.
PMS - Stock / MaxMix Thumbscrews (updated 01/30/09)
For Carb Tuning - One Stock PMS Trun EQUALS 1/2 OLD Style MaxMix Turn (2 to 1 ratio) New one Same as Stock
When you rejet the carbs you will need to drill out the cover over the PMS screws, which are inset into the bottom of each carb. Once done rejetting, you can (but not easily) do your final tuning with the "buried" PMS screws, or you can replace them with the MaxMix PMS screws. They protrude out of the bottom of the carbs, making it much easier to adjust with your finger -- or, better yet, a 1.5 to 2.0 inch long piece of rubber hose - with the right ID to fit over the thumb screw head of the screws. In my case, big fingers and hands made the "rubber hose" trick a necessity.
Some people don't like the MaxMix screws, because they have a faster/sharper taper than the stock screws, and therefore are not as fine for adjusting. However, most who have them swear by them - and personally I have had no problem. Note: Max Air is now shipping a new style that has the same taper / profile as stock - much finer to tune with, plus long stem for tuning.
Stock and Old Style MaxMix PMS screws
(click pic for larger pic)
Aftermarket Thumb Screws:
MaxMix - Available from MaxAir
Alternate Vendor - see Pilot Thumbscrews -- follow the link
Caution:
Be careful, very careful when reinstalling your carbs if you are using newer version of the MaxMix PMS screws. Pulled my carbs and checked the PMS setting I had done a few days before and found the rear was dead on, but the front was 0.75 turns further in that I had set it. Sure enough - the front cylinder PMS screw sticks way out/down and is right where it will hit the intake manifold rubber collar thingie as you snake the carbs back into place - and I didn't see it because I always stand on the left side when doing the install and the PMS is hidden. Not this time - leaned way over and watched like a hawk, saw that it would hit easily, and took extra pains and finally got past that "PMS shifter" and wrapped it up. -- from SilverBack
Stick with Stock PMS Screws?
If you decide to use the stock screws, the right tool will make it easy to do the adjustments (if I knew about this tool ahead of time, most likely would have NOT gone with the extended screws!). Courtesy of the ever helpful Daddo, here's a link to the offset Pilot Screw Adjusting tool - $30 and does the trick.
http://www.motorcycle-superstore.com/item.aspx?style=8015&department=646&division=6
Same tool available here $20 - http://pitposse.stores.yahoo.net/popiscadto.html
Another tool - for only 7 bucks!! (Thanks to Vstar_in_NH)
And Another Solution - rosskp: Here is a picture of a screw that I soldered using an old pilot jet, can be done with JB weld, an Metal Epoxy. Make sure you don't get any on the threads. (Note: rosskp uses a fuel line hose to grip the add-on to the screw - making it easier to grasp and twist in the confined space.)
And another: mitchyd - drilled and taped the PMS screw ran a nut up the small screw/ bolt against the head with a star washer for grip JB weld into place so doesn't vibrate apart:
And another: Tundrawolf: I used a 1" Copper Rivet (Hardware store 25c a piece), Oatey Water Soluble tinning flux (for joining dissimilar metals) (Lowes Under $3 I think), a cutoff disc on my Dremel to shape the end of the Rivet -- The final result was a small slit that fit snugly into the notch of the mix screw. Maing sure of the best alignment BEFORE trying to solder the two pieces, it is best to hold the tip of your high wattage soldering gun mostly to the rivet, and partially to the PMS screw, if the rivet is on the bottom-as heat rises.
imnezrider (mdpar3) - Socket/driver bit...beats the heck out of pullin' carbs.
Tim B's PMS Needles, with Finger Turn Heads: http://www.metric-magic.com/
PMS Screw Location:
Stock PMS screw cover location Aftermarket PMS installed
Helpful Hints on Install:
SilverBack - Take it Easy
Go slow -- follow both sets
of directions (MaxAir's and CycleForay's) - you'll do fine and it will
take you about 3 or 4 hours max
Be extra careful of the 8 float bowl screws - they are soft headed and
will tend to strip if not careful.
3 suggestions:
-- get a really good,
properly sized Phillips head screwdriver, place it in the screw head,
give a tap or two with a light hammer to ensure the driver is seated
well - apply plenty of downward pressure (see next item for proper base
to work on
-- get yourself a big roll of duck/duct tape - not to tape with, but to
use as a stand to set the carb pair on - to give yourself a stable
platform for the application of downward pressure on the screws as you
turn them out.
-- and, get yourself a small pair of needle nosed vice-grips - they will
let your tightly grip any stripped screw head for final removal if you
have a problem. Plus this is a valuable tool to have with you at all
times!
If you are not doing this yourself, a competent dealer mechanic should be able to do this whole thing in no
more than 2 hours - so use that and the dealer's rates to guesstimate
the cost of going that route - and ask for a firm quote to do the work!
But, don't be "afraid" of trying this - it is a snap -- really! PS -
As a novice, I
did the jetting and put on a new set of pipes - all in 2.5 hours
Carb Bowl Cover Screw - Caution
NOTE: One thing to be careful of when opening up your carbs - the 8 screws that hold on the bowls are SOFT and subject to buggering easily. Here's some advice that bears following:
Skypirate: I've read several posts about stubborn float bowl screws and thought I would share this with ya'll. I'm an aircraft mechanic which means I spend WAY too much time dealing with boogered up Philips heads. Small aircraft have thousands of 'em and I find that the last guy to close those panels just doesn't care if I'm the next guy to open them. So I keep a can of coarse valve grinding paste in my tool box. Just dip the tip of your screw driver in the paste and it gives it a fantastic grip in the screw head. Also a bit of a tap on the end of the screw driver with a hammer will help to brake the screw free.
Permatex makes a water based compound that's pretty easy to find. It comes in a tube and you can get it at just about any auto parts store. I like the oil based stuff best and I think I got my last can at NAPA. Small can will last almost forever.
For you guys that are just starting out with your tools get a screwdriver that uses replaceable bits and toss the bit as soon as it shows any wear. Nothing can wreck a Philips head faster than a worn bit.
SilverBack: if you do screw up a screw head: try attaching a vice-grip pliers to the shaft of your screwdriver, holding it firmly with one and pressing in on the driver and the other twisting with the vice-grips - this can be aided with a tap on the screw as noted in Skypirate's comments.
Throttle Valve "Finger" Emergency Repair
If you break off one of the little plastic 'fingers" - here's a fix Jack Phelps
Single Carb (updated 09/25/06) BACK TO INDEX
KJS Single Carb Manifold - Visit KJS Owners Forum Visit KJS Motorcycle Works
Comments by White Wing (latent_image):
-- Low end torque is improved and moved
lower in the rpm band but peak HP is pretty much stock.
-- A lot
of the folks are experimenting with different carbs and working out
the details. A roadie carb is pretty popular as well as some flat
slide carbs.
-- The install of the actual manifold is a very
touchy procedure. The manifold is rigid and connects to both
cylinders and has to be bonded in place and small errors results in
air leaks and a do-over with a 24 hour cure time. Kind of fussy
procedure.
-- You know the way the kit comes you are supposed to
dismantle you stock carbs, separate them and drill out some jets,
not for the faint of heart. LOL
Comments by Vstar_in_NH (Jack Rosa):
I've done a lot of DYNO work with the KJS. The KJS will give you
such a boost in torque if you are not holding onto the bars tight
you'll fall off. I've run the pod style air kit and the KJS, dynoed
both and my peak HP was within 2 hp, BUT the torque was 89lbs with
the KJS! The bike will launch off the line HARD. The torque is so
awesome that you just roll it on and the bike goes. No down
shifting, fantastic for touring in the hills or rippin on the slab.
The best combo I've found is the KJS with a used 40mm flat slide HD
replacement carb. I got 92lbs torque and 56hp! The best part, the
sound! I pull into a parking lot full of other bike HD, etc and they
all look at mine and usually come over to see what I've got in her.
Check out my website, I have movies so you can see and hear the
setup. DYNO charts, reviews, pictures, etc.... For a stock engine
nothing gives you pull/acceleration like the KJS. Another cool thing
is it cleans up all the crap between the cylinders and runs cooler.
You can put air horns under your tank too.... Ohhh ya, no more
synch'n. His web site:
http://vstar1100.froggbox.com/kjs.htm
Reality - Tradeoff's - Comments by KROME STAR (GatewayStar)
In one of these KJS posts, someone
mentioned trying to use the KJS to improve low end torque, and high
rpm cams to hit the other end of the spectrum....just wanted to
point out that it won't work. I had considered the same idea at one
point, but had to dismiss it. You'd be pissing your money away on
the cams, as they won't have the desired effect on top end.
Why? Because the KJS flows like crap. Not that it's Ken's fault -
you simply CAN'T flow air well with a 90+ degree bend in your intake
system/head port. The manifold helps low end power because of a
widely known principle...longer runners aid in power production at
lower rpms. Just make sure you know that for every bit of added
power down low, you are giving it up later in the power band. In
this instance, there is no "free" power gain. Unfortunately I don't
have charts specific to this situation to illustrate, but given the
angle of the port and the necessary design of a single carb
manifold, it's elementary science that laminar flow goes out the
window at higher RPMs.
That said...what do you want from your
engine and mods? Typically one seeks one of two goals - peak hp or
torque in a given range, or most added power 'under the curve',
referring to the Dyno graph. In the case of a single carb manifold,
you will get greater power numbers in the lower end of the rpm
range, but your curve will dive below stock somewhere mid graph.
The alternative is cams and high compression pistons - they'll
add power through the entire range. Roughly the same investment in
parts, but it does involve pulling your cylinders, which is
typically a more challenging task for most DIY wrenchers. The payoff
is more power under the curve, usable across the entire power band.
While stronger than stock down low, it will likely not match the
numbers available with the single manifold option. It can't, as the
short intake length limits those numbers. But that same short run is
responsible for greater gains in the higher rpm range.
Obviously there is a niche market that demands more torque from the
V-Star engine, designed for mid-range oomph, even at the expense of
usable power later in the power band. But there seems to be a bit of
evangelism going on here, and I'm afraid some folks are going to be
influenced to make a power band trade-off they ultimately aren't
happy with.
Gary
Cruzmystar
KJS Install and Comments - thread link
(added 05/17/07)
Jack's Page on the Install of the KJS
KJS Measurements - The Real Test
Jack's Dyno Runs - http://vstar1100.froggbox.com/Dyno.htm
Discussion Thread on this topic:
http://forums.delphiforums.com/yamaha1100/messages?msg=51822.1
KJS "Dyno" - from vstar105 - KJS ported intake, reworked 40mm roadie carb, hard krome 2.75" pipes, and ported intake and exhaust. Stock coils could not handle 5k rpm, but it is a blast to ride and get's mid 40's mpg.
NOTE: Appears to be from portable "Drag Race" machine and so is "suspect".
Fuel Injection (updated 01/25/07) BACK TO INDEX
Nothing available at this time.
Some initial work was performed by Jack LaRosa up in NH, but progress was suspended due to that age old :bugaboo" of progress - $$ and time. perhaps someone will pick up the ball and move this forward.
Turbo Charging (updated 12/29/07) BACK TO INDEX
Nick (cruzmystar) has done it!! Turbo 1100!!! Announced at 2:36 pm 12/129/07 in this thread on the forum:
http://forums.delphiforums.com/yamaha1100/messages?msg=29920.1
His comments from the first post in the thread:
Well, for the most part it's done. I've got some small little things to do left but it is up and running.
Eventually I'll replace the intercooler with a custom sized one (much smaller) as this one is a little big but for now it was relatively inexpensive and will do the job. Paint still needs to have the final cut and buff as well. Once we get a little bit nicer weather I'll get it out on the road for some more tuning. Then it's off to the DYNO.
I'm shooting for around the 120hp range. In theory, if everything will hold, it could put out 130-140hp but I doubt I'll push it that much. I'll probably start the tuning at around 5psi of boost and end up at around 7psi.
Here's some of the more technical stuff for those that are interested. It's a Garrett GT15 turbo pushing through an HS40 carb (for now) and a custom intake manifold. I decided to built an intake myself to solve the uneven runner length/diameter issue with the KJS intake. I think i can get it tuned in with the HS40 but i think eventually I'll put an S&S carb on there because i am a little paranoid about the slide sticking in the HS40 when i put a lot of boost to it.
I also need to give a special thanks to the following people for helping me make this happen either with parts to just sharing knowledge.... Rick Zlacket at (Honeywell/Garrett), SS custom cycles, AGP Turbo, Dave Boyd (top fuel drag bike builder), Stahl's headers, Rob Appell (Painter), Nick at Trask Performance, and everyone else who I'm forgetting.
~nick
Pictures of "Hitman":
Dyno Results - Tuned Up - from 10/18/08 Cruzmystar post:
Finally! It only took a little over a year but I made it down to the Dyno today. Spent almost 5hrs there getting the bike tuned in but we did it!
112.05hp and 102.65ft/lb of torque! Man, what a stinkin' rocket! Not quite the 120hp I wanted but overall I'm very happy.
This run was on the SAE setting and with the smoothing at 5. That's a pretty conservative setting and I think is the most realistic. Uncorrected hp was about 116 but I think that's cheating and most people thinks it's more fair to compare numbers at SAE. At least we now what a stock engine is capable of holding up to because that was at 19.5psi of boost which is WAY more than I was planning on putting to it but I just had to get well over the 100hp mark.
BG! As you can see the torque curve is insane holding max torque from about 4000rpm all the way to 6500rpm. I ran the bike on 110 octane fuel just to be on the safe side and it's now tuned down to 92.5hp and 12psi of boost so I can run 92 octane in it.
At one point I had the boost up to 22psi but the hp started to drop and exhaust gas temp was reaching a melt down level so we found the max flow for this turbo. I think with a bigger turbo I could easily get into the 120-130hp range but I'll sacrifice the quick spooling that it does now so I doubt I'll change it. Last run of the day after we tuned it down and it finally ate the front cylinder's coil so new coils and wires are now needed. At least nothing on the inside saw the light of day so I'm happy!
I think the only future changes will be switching back to a flat slide carb. Not a big fan with the S&S that I've got on there now. It's a tad too big and doesn't have near the neck snap at initial crack that the Mikuni did. Another thing to learn from all this is it really proves a point that the intermediate shaft isn't a weak link in itself and the failures are more of a fluke thing than anything.
Here's an older thread - A thread on turbo ideas
Air Cleaner Replacement (functional/cosmetic) (updated 03/17/08) BACK TO INDEX
Faux Hypercharger Install
(LINK IS BROKEN)
"S&S" Style Air Cleaner vstar1100.com/Jack Phelps
Metric-Cruiser.com 1100 AC covers (Broken Link)
Air Scoop Dog Bowl Mod - Tony Anzalone - click here
2006+ / Catalytic Converter Models - Special Carb Work (updated 08/15/11) BACK TO INDEX
Discussion - General Instructions - How To Do It! Discussion Threads
2006 & Up Discussion - General: BACK TO INDEX
The '06 & up model carbs are different than prior years - to meet pollution abatement needs and include a mechanism that alters the "standard" approach to jetting with "big air modifications" such as PODs. (In addition, the 06's have a different interface plug to the igniter unit, so the DYNA3000 can NOT be used -- BUT there is now a unit available from DYNA for these bikes!!.)
Close inspection of the carbs reveals the following: a revised, taller main jet holder than includes an O-ring; some added restriction in the fuel flow in the bowl at the base of the jet holder; and a solenoid that appears to restrict fuel flow under command of the igniter unit (?). It has also been observed that the rev limiter has been increased (under some as yet to be fully determined conditions) up to 6800rpm. Hearsay comments indicate Yamaha says the solenoid is to shut off the fuel in tip-over conditions to avoid fuel fires - with the hot catalytic converters.
So far there are 2 approaches to modifying the carbs of 06 bikes to improve performance:
Replace the 06 plus stock Main Jet Holder with one intended for 05 and prior bikes.
Grind off the added metal on the top of the stock holder at the same time removing the added O-ring - more below
More info on "how to" details is published below.
Jetting:
Over time, we have come to realize that the original jetting changes for these bikes and PODs was using jets that were way to big - repeated Dyno runs have come to prove that, once either of the above mods have been completed, there is no difference between the pre-06 and post-06 (solenoid) bikes. The tables for the bigger jetting have been maintained below (and if your bike runs fine with those setting, you're OK), but it is recommended that you use the non-solenoid jetting once the mods have been made.
Discussion - SilverBack:
The original pioneers of the Maximum Effect mods are owed credit for getting the ball moving. Unfortunately, they moved forward too many steps at a time and did not use Dyno testing of HP and torque, thus leaving us in a situation where several things came up "short":
More mods were being made to the carbs than were required - including some that could have been very expensive if one were to miscue just a bit.
The use of jets that were much too large.
Both of these problems have been uncovered and resolved as documented below.
|
Best Way to achieve Maximim Effect Mods:
|
|
Subsequent testing shows solenoid bikes with Max Effect Mods should be jetted the same as non-solenoid bikes Over time, we have come to realize that the original jetting was using jets that were way to big in many cases - repeated Dyno runs have come to prove that, once the Maximum Effect Mods have been completed, there is very little, if any, difference between the pre-06 and post-06 (solenoid) bikes.
The tables for the bigger jetting have been maintained below (and if your bike runs fine with those setting, you're OK), but it is recommended that you use the non-solenoid jetting as a starting point once the mods have been made.
|
2006 - Max Performance Instructions - How To Do It! BACK TO INDEX
 |
 |
|
 |
 |
|
NOPE: Don't do it this way
Do it Tim's Way |
Holder-Jet in Carb |
Solenoid DO NOTHING |
Tim's way (below) |
Diagram |
For reference only: Pictures of the 05 & 06 float bowls:
click for bigger image
Tim's Way to Mod Jet Holders - Another, Easier Way Metric Magic (TimB1007)
-- Just grind off the top of the holder, down to the bottom of the top O-ring groove - easier, just straight grinding.
You are grinding off the part of the holder that has no threads, merely is a sleeve around the sides of the jet.
Threads begin below the part ground off. See Pix above.
What follows is no longer the preferred approach
- See above for easier, safer approach - proven to make the solenoid bikes tunable tha\e same as non-solenoid bikes.
The jet holder mod is very,
very easy!
The jet holder mod:
-- remove it from the carb,
-- remove the main jet from
it,
-- remove the O-ring,
-- install the jet holder in a
cordless drill or electric drill,
-- while spinning it in the
jet holder in the cordless drill against a running grinding wheel,
-- grind
the O-ring lip at the end of the holder, down to the OD of the main jet.
(see pic above)
-- you
could actually leave the main jet in place if you want to protect where
the jet seats to the holder.
-- this mod makes a lot more
clearance for fuel to flow to the main jet
-- once you see the fuel bowl it becomes much clearer.
-- install your new jet
-- reinstall the jet holder
-- repeat for the other carb
Another, Easier Way Metric Magic (TimB1007)
-- Just grind off the top of the holder, down to the bottom of the top
O-ring groove - easier, just straight grinding.
You are grinding off the part of the holder that has no threads, merely
is a sleeve around the sides of the jet.
Threads begin below the part ground off.
The fuel bowl mod:
-- needs to be done with
CAUTION!
-- remove bowl from the carb
-- remove solenoid from the
side of bowl
-- look through the threaded
solenoid mounting hole,
-- you will
see a very small hole which the needle on the solenoid closes when
activated
-- drill that hole out to 3/16
inch- CAUTION! READ STEPS BELOW
-- use a
piece of tubing, brake line, aluminum tubing, copper tubing, etc
-- that
will fit over the drill bit AND also inside the threaded hole in the fuel
bowl.
-- this
will protect the threads for the solenoids.
-- drill
slowly, and carefully!
-- take
your time!
-- Note:
two ideas since this was done:
-- Sleeve should be .210 ID and .240 OD (assume inches) (twodogs)
-- Or: Wrap the drill bit with electrical tape - ClassicSteve used "about
4 - 5 wraps".
-- screw the solenoids back
in.
-- now even when the solenoid
activates, it can't shut fuel off to the main jet.
Jetting:
Solenoid Wires - They Break Easy - How to Fix
Comments From Brad (bdc1964)
Side note for you '06ers: The wire leads to the fuel cut off solenoids are not secured very well. From repeated removal and installation, I broke one off last night. After I scraped out the black seal material on solenoid, I soldered the wire back and sealed it with JB Weld for good measure. Didn't feel like spending $150 on something I don't really want working in the first place, however, you will get a check engine light
Removing the Solenoids Entirely (updated 08/18/09)
This discussion was part of the original, no longer needed / supported "fix" for Solenoid-Carbed Bikes (see yellow box above).- revived for those who break the wires or want to remove the solenoid stuff entirely for some other reason..
You can remove the solenoids entirely, but there are several things you will need to do:
You will need to insert a bolt in the hole from which the solenoids were removed - the 8mm socket head fits fine, the head fits into the recess in the carb. An 8mm x 5mm (thread pitch of 1) will be perfect & I think it looks better than the big brass plug. Even better, I can order the correct screw & gasket to fit. I'll order 20 tomorrow. (courtesy of TimB007)
You will have to "put up with" the check engine light being on
OR - Add some electrical stuff to make the bike think the solenoids are a still there.
catnipp Amie (catnipp2):
Make a new harness to eliminate the fuel cut off solenoids . I made a wire harness by cutting the wires about 6'' from the solenoids. Then soldered each wire to a 39 ohm resistor (or 33 ohm OK too) and then put the other end of the resistors together and soldered a wire on , put a eyelet on the end and grounded it. I used the screw on the valve cover for the ground. (Note: Resistors from Radio Shack - in the Drawers $1 or less each).
But, if you have to run the TPS (Throttle Position Sensor) - ONLY required if you use KJS single carb manifold
catnipp Amie (catnipp2):
I made the bracket out of flat stock aluminum and mounted it to the bracket where the stock air box bolted right under the gas tank. I used JB Weld to attach a small blade that fits into the TPS at the center of the bell crank. I assembled it all then applied the JB to hold it in place until it cured! OVER NIGHT ! Then I re-aligned it and tightened it all up to make sure nothing was out of alignment while twisting to full throttle slowly. . IT WORKED !!!!
2006 - Carb Mod discussion threads: BACK TO INDEX
2006 Carbs on an 1100 Classic 2006 Dyno Run Cobra 2 into 1 BEAK
HELP - just installed pod kit and pipe V Star 1100 Cobra 2 into 1
Carbs (updated 03/05/11) BACK TO INDEX
Carb Discussion BACK TO INDEX
Reading
Carb Theory 101 - Norwestars Article - http://s180867979.onlinehome.us/docs/carb101.pdf
Motorcycle Cruiser Magazine Jet Kits & Carb Basics
Jetting Instructions - Pictures - Steve Schneider, CycleForay
Carb Schematic:
Jetting 101: (updated 06/19/11) BACK TO INDEX
Note: Not all carb manufactures call parts the same name. In above drawing
Pilot air screw and jet = PMS screws
Throttle valve cutaway = Pilot Jets in terms of working range
Needles = Needles
Main =Main
Other Jets - ones we do NOT change:
Pilot Air Bleeds - no change except to undo mistakes by poor jetting
Starter Jets - Used by the starting process, advancing the "choke" / enricher lever opens access to this jet, enriching mixture to aid in starting.
)
Excellent Jetting Article (DIY or Supplement Mfgr Instructions
-- Courtesy of Steve at www.CycleForay.com (new link due to site missing)
(Added here 1/5/08)Note: It will be difficult to remove the float bowl screws without damaging them. If your kit didn’t come with any, I suggest that you purchase some. The best choice would be a stainless steel Allen head cap screw… M4-.7 pitch, 10 mm long. You will need (8) of these total. Don’t forget to get (8) lock washers too. Using your needle nose vise grips, break free the four screws that hold the bowl on. Once free, you can use your Philips screwdriver to remove them completely.
Adjusting PMS and Needles:
PMS (Pilot Mixture Screw):
In (clockwise) = Leaner
Out (counter-clockwise) = Richer - you are turning the taper of the screw away from the "opening" and allowing more fuel to pass.
More Info:
The question was what direction does what when you turn the PMS screw? The short answer is outwards make it rich inwards makes it lean.
The PMS screws taper to a point. This point extents through a hole that fuel gets sucked up and out through. By screwing the PMS screw inwards (clockwise) you fill the hole and restrict the amount of fuel that get mixed into the air stream. By unscrewing the PMS screw (counter clockwise) you remove the restriction from the hole allowing more fuel into the air stream.The difference between the Stock PMS screw and the Old Style MaxMix screws are how fast they taper to a point. The old style MaxMix does it much faster, so if a stock PMS screws is 3 turns out the MaxMix is 1.5 turns out. New MaxMix screws have the same taper as stock, and should be adjusted that way.The start position for the stock PMS screws on a V Star is the number of turns specified above in the jetting tables - out from lightly seated. Lightly seated is when you feel the rubber "O" ring on the PMS screw start to compress.A suggested adjustment procedure - "lean drop": (from Drostar100)Sync the carbs first.
If you think you need to adjust them PMS screws you need to drill out the brass caps that seal them, this requires removing the carbs. Drill a small hole in the cap and either wiggle the plug out with the drill bit or use a sheet metal screw to pull them out.
Screw the PMS screws both in until they are lightly seated counting the turns on both screws to see if they are equal.
The next part is up to you.......A) if you think you can tune it by ear then run the screws out about 3 turns, run the bike and see if you have popping on deceleration, if you do then turn them out in 1/8 increments until the popping goes away and you will be close enough for government work. Re-sync the carbs after doing this.
B) If you have a tach, start at 2-1/2 turns out and gradually increase the turns on each screw evenly until the idle drops then go back in slowly until the idle comes up.
That is called a "lean drop". You turn the screws until the idle drops and then lean it out a bit.Needles: Removing shims = Leaner - Adding shims = Richer
Similar to above, you are moving the taper away from the "opening" and allowing more fuel to pass. Note: For
Needles with notches and clips, UP = Leaner, Down = Richer
Moving the clip UP = Leaner, Down = Richer - as you are allowing the needle to move down Less! - (both refer to clip position relative to the top or blunt end of the needle)
Stock Needle Part Numbers
OEM part numbers for needles - Look down this page under the needle pictures:
(updated 03/03/08)
Pod kits come with the jets you will need. for the kit and MOST exhaust systems, as well as instructions on which jets to use and how to set PMS and Needles.
With higher performance 2 into 1 systems (such as the Cobra 2 into 1) you will need other jets - the Cobra 2 into 1 needs either 147.5 or 150.0 jets with 150.0's appearing to be the jets of choice - at of the time this was written (will update as new info (Dyno runs, etc) emerges).
POD (& Other) JETTING, SETTINGS (6) (7) (8) (updated 10/08/09) BACK TO INDEX
- THESE SETTINGS ARE PLACES TO START - MOST BIKES WILL RUN WELL WITH THESE SETTINGS.
- PERFECTION WILL ONLY COME WHEN YOU ARE PLEASED WITH THE WAY THE MACHINE RUNS
- AND WHEN THE DYNO GIVES YOU THE BEST AFR, HP AND TQ
TABLE A PRE-2006 BIKES (EXCEPT CALIF. '05's) AND all Solenoid bikes with Max Effect Mods(11)
|
INTAKE |
PIPES |
PILOTS |
MAINS (1)(10) |
Stock PMS & New MaxMix PMS (since early 08) (2) |
MaxMix Old PMS Pre 2008 (3) & Tim's PMS |
Stock needles (4) Shims below C-Clip |
Pro needles (5) C-clip notch (from top) |
|
Stock |
Stock or Slip-on |
17.5 |
112.5F 110.0R |
2.0 |
n/a |
Plastic & 0.020 |
n/a |
| Full | no change | 115.0F 112.5R | no-change | n/a | no change | n/a | |
| Performance (9) | no change |
117.5F 115.0R |
no-change | n/a | no change | n/a | |
|
PODS |
Stock |
20.0 |
145.0** |
2.5 |
7/8 |
Plastic & (2) 0.5mm |
1st notch & plastic spacer |
|
|
Drilled Stock |
20.0** |
145.0/147.5** |
2.75 |
1.0 |
Plastic & (2) 0.5mm |
2nd notch & plastic spacer |
|
|
Slip-ons w/baffles |
20.0/22.5** |
147.5** |
2.75-3.0 |
1.0 |
Plastic & (2) 0.5mm |
2nd notch & plastic spacer |
|
|
Full System |
22.5 |
150.0 |
3.0-3.25 |
1.125-1.25 |
Plastic & (2 to 3) 0.5mm |
2nd notch & plastic spacer |
|
|
2 into 1 |
22.5 |
150.0 |
3.0-3.25 |
1.125-1.25 |
Plastic & (2 to 3) 0.5mm |
2nd notch & plastic spacer |
|
|
Performance (9) 2into2 or 2into1 |
22.5 |
150.0 |
3.0-3.25 |
1.25-1.50 |
Plastic & (2-3) 0.5mm |
2nd notch & plastic spacer |
** Value updated 08/07/09 - Reflects latest experience, influenced by ethanol prevalence
Subsequent testing shows solenoid bikes with "Max Effect Mods" should be jetted the same as non-solenoid bikes - See boxes above for best way to achieve "Max Effect Mods".
Over time, we have come to realize that the original jetting was using jets that were way to big - repeated Dyno runs have come to prove that, once the Maximum Effect Mods have been completed, there is no difference between the pre-06 and post-06 (solenoid) bikes.
The tables for the bigger jetting have been maintained below (and if your bike runs fine with those setting, you're OK), but it is recommended that you use the non-solenoid jetting once the mods have been made. (Modified 07/24/10)
Notes:
1. Mains - Stock bikes come with staggered mains. Consensus on POD is to use same size mains front/rear.
Note: MaxAir recommends staggered Mains with Pro needles, but forum consensus is to use same sized mains, even with Pro needles. We suggest you do it the MaxAir way if you are going to use them for customer assistance, etc.
2. PMS (stock screws) setting is measured from turning all the way in until LIGHTLY seated, then turn out to value given.
MaxMix NEW (since early 2008) have the same profile / slope as stock - so they are set the same as stock.
3. MaxMix (Old) screws setting is measured from turning all the way in until LIGHTLY seated, then turn out to value given. MaxMix (old ones) screws have steeper slope and therefore require fewer turns.
& Tim's PMS - same applies.
4. Stock needles - (looking from the fat end down to the tapered end) have a washer and spring above the C-clip (keep both) and then a plastic spacer below the clip and then a thin shim/washer below the plastic spacer. For pods, remove the lower spacer and retain the plastic spacer, then add the specified shims below the plastic spacer.
5. Pro needles - (looking from the fat end down to the tapered end) will use the stock spring and washer above the C-clip and also use the stock plastic spacer below the clip and discard the stock spacer from below the stock clip.. They do not use other spaces, because they get their variation from the notch setting for the C-clip. Set the C-clip placement as specified (and be sure to use the stock plastic spacer below the clip).
6. Altitude Impact - The table settings are for altitudes of up to 4000 feet above sea level. For 4000 feet and above, reduce main and pilot jets one size (jets come in 2.5 increments) -- except for Pro needle use, then only reduce main jets one size.
7. Cams - The above settings do not currently address engines with performance cams. See Cams info below.
8. 06 & newer plus 05 Calif. bikes -These setting apply to '06 bikes that have had the o-ring removed and both the jet seat and the solenoid mods both performed - they do NOT apply to '06 bikes with only the o-ring removed.
9. Performance Pipes: Current list includes: Cobra HP 2-1, PCS Monster Pro 2-2 (despite looks), Roadhouse Classic 2-1, Pro-Race Pipe by S&S Custom Cycle 2-1 and . . . . (See HP Gain Section)
10.Altitude Adjustment - Main Jets - drop one size for every 2000-3000 feet rise in elevation
11. Solenoid bikes - with replaced or modified Main Jet Holder - treat the same as non-solenoid bike
(Settings for Stock Intakes Are Still Valid!).
Except for Stock Intakes, The Following is no longer valid (see above comments)
TABLE B
2006 AND LATER BIKES (AND CALIF. '05's)ONCE THE JET HOLDERS ARE MODIFIED AND SOLENOID HOLES DRILLED(11)
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POD SETTINGS NO LONGER VALID - STOCK INTAKES INFO STILL VALID- SEE TABLE A ABOVE FOR JETTING FOR SOLENOID BIkES WITH MAX EFFECT MODS TABLE RETAINED FOR HISTORICAL REFERENCE - SEE COMMENTS ABOVE FOR REASONS FOR THE CHANGE. |
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INTAKE |
PIPES |
PILOTS |
MAINS (1)(10) |
PMS & New MaxMix (since early 08) (2) |
MaxMix Old Pre 2008 (3) & Tim's PMS |
Stock needles (4) Shims below C-Clip |
Pro needles (5) C-clip notch (from top) |
|
Stock |
Stock |
17.5 |
115.0F 112.5R |
2.0 |
n/a |
Plastic & 0.020 |
n/a |
| Full | no change | 117.5F 115.0R | no change | n/a | no change | n/a | |
| Performance (9) | no change | 120.0F 117.5R | no change | n/a | no change | n/a | |
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S&S Performance Needles in Non-Cammed bikes: (updated 05/16/08)
Bikes with SS 429 05 420 or 424 cams: For Both: Non Solenoid CarbsNon-California, Non- Catalytic Converter Bikes:
Stock float levels - Full replacement pipes20 pilots3 turns PMS
1 shim on our SS needles140, 142.5 or 145and Fully Modified Solenoid Bikes (see above) (updated 06/19/11)
Shane's 4/29 / 420 / 424 Jetting - with SS Pro Needles
Updated for ethanol fuel (the 22.5 pilot jet is dead and gone)
429 / 420 / 424 Cam Kits: With Stock needles (For Full Exhausts)
20 Pilots
1 additional shim per needle **
3.25 to 3.75 turns out on stock PMS with stock float level & 20 pilots (Start at 3.5)
157.5 or 160.0 mains (Start with 157.5)
429 / 420 / 424 Cam kits: With SS Performance needles (For Full Exhausts)
20 Pilots
SS needles 4th clip plastic spacer no shim unless needed **
3 to 4 turns out on stock PMS with stock float level & 20 pilots (Start at 3.75)
157.5 or 160 mains (Start with 160)
** From top of the needle to the point: Washer, clip, plastic spacer, our shim if needed.(Top washer & plastic spacer from stock)
Following is no longer valid:
For reference Shane's range of settings in preserved below:
Non-Solenoid Carbs: (Recommended starting points) (No Data/Settings fro Drilled-Out Solenoid Bikes)
420 & 424 Cam Kits: With Stock needles (No Slip-Ons)
152.5 or 155 mains with stock needles (Start with 152.5's)
17.5, 20 or 22.5 Pilots (float level determines jet) (Start with 20's)
2 to 3 shims per needle (.040 to .060 Start with 2)
Stock float levels - Full replacement pipes
2 to 3 turns out on stock PMS with 20 pilots (Start at 2.5)
3 to 4.5 turns out on stock PMS with 17.5 pilots (Start at 3.5)
2 to 3 turns out on stock PMS with 22.5 pilots (Start at 2.5)
420 & 424 Cam kits: With SS Performance needles (No Slip-ons)Note: Due to Ethanol formulations now in use,
bikes tuned well last season in this category are having to:
-- Increase 17.5 pilots to 20.0 pilots
-- Increase main jets up by 1 size
Per Shane 0n 07/24/09
152.5 or 155 mains (Start with 155 first)
17.5 or 20 Pilots (Start with 20's at 2.75 turns first)
0 or 1 shims per needle (Start with no shimming)
Stock float levels - Full replacement pipes
2 to 3.25 turns out on stock PMS with 20 pilots (start at 2.5)
3 to 4.5 turns out on stock PMS with 17.5 pilots (Start at 3.5)
** From top of the needle to the point: Washer, clip, float, then shim only if required.
(Top washer & float from stock)
502 performance kits: Stock carbs (Must use full exhaust)
152.5 or 155 mains (Start with 152.5's)
20 or 22.5 Pilots (Start with 20's)
2 to 3 shims per needle (.040 to .060 Start at 2)Stock float levels - Full replacement pipes
2 to 3 turns out on stock PMS with 20's (Start at 2.5)
2 to 3 turns out on stock PMS with 22.5 (Start at 2)
Dyna Settings With Cams
We suggest starting with curve 6 and trying curve 5 as well (TPS disconnected)
429 & 420 & 424.... 7000 Max rpm
502 all......... 7500 Max rpm (8000 with NOS)
Tweaking Carb Tuning for Cammed Bikes: (from Shane)
For those that are having issues with popping on deceleration with 20 pilot jets here's my recommendation.
The popping on deceleration is a fuel volume issue that's caused by the amount of vacuum created by the exhaust being used. Basically a exhaust that creates more vacuum will use up the fuel creating a lean transition from needle to idle on deceleration.
Starting with a 20 pilot and 2.5 turns out, try to clean this up by opening the screws 1/4 turn at a time. If the stumble starts to return then drop to a 17.5 and start with 3 turns out. Then opening the screws 1/4 turn at a time until the issue is corrected. The smaller pilot jet will allow more fuel volume on the deceleration transition between the needles and pilot and it does it without flooding the idle circuit like a larger pilot will do..
The PMS screws can be turned out as far as 4.5 turns before going up to the next jet size. Hope this helps some of you that are close but, just can't get it.
Thanks, ShaneSolenoid Carbs: (More info needed) (See Note 11 above) (updated 04/17//09)
SS 424 Cams SS Needles Solenoid Bike
Thread from: First "guinea Pig":
navistar71 (ziggy6050) Installed Shane's SS 424 cams and SS Needles on 07 Classic - Click Here
Now at: RU600 PODS - All Carb Mods Made - 424 Cams
167.5 mains, 17.5 pilots, 3.5 turns on PMS,
SS needles set to the center clip position,
1 SS shim and the stock plastic "shim"
(Updated 10/20/11)Stock Needles - How They go Together: (Thanks to DSWANZ)
Picture of Carb Slide and needle and needle holder - and the O-ring you need to be careful to keep.
(Click for larger picture)
IN THE DIAGRAM BELOW, YOU MUST REMEMBER THAT THE NEEDLES ARE INSTALLED IN THE CARB WITH THE NEEDLE (LEFT SIDE OF DIAGRAM) POINT DOWN INTO THE CARB, AND THE BIG SPRING (RIGHT SIDE OF DIAGRAM) IS ON THE TOP OF THE CARB. THIS IS OBVIOUS ONCE YOU HAVE THE CARB OPEN AND THE NEEDLES TAKEN OUT - BUT IS NOT OBVIOUS UNTIL YOU DO.
MaxAir & DynaJet Needles
SHIMS / WASHERS GO UNDER THE PLASTIC SHIM/SPACER/FLOAT - TO THE LEFT OF IT IN THE ABOVE DIAGRAM!!
EVERYTHING TO THE RIGHT OF THE PLASTIC SHIM/SPACER/FLOAT STAYS AS IS, AND ALL THE ADDS - DELETES ARE REFERENCING THE ITEMS TO THE LEFT OF THE PLASTIC SHIM/SPACER/FLOAT
Note: Depending on who is typing , where they came from, what they heard - the white plastic "thingie" on the needle is variously called a "plsstic shim", "float" or "spacer" - I refuse to call it a thingie - so it is referred to above as SHIM/SPACER/FLOAT.
Note: you have to
watch buying stock needles from yamaha. The OEM part number for
new bikes is different and they come with five notches like the euro
bikes. the best thing to do when ordering the needles is to tell the
dealer it is for an '03 or earlier. stay away from '04 and '05 since
the California bikes are different.
OEM part numbers for needles:
'06 and later - 5EL-1490J-00-00 - five notches
'03 and earlier - 5EL-1490J-20-00 - single notch
'04 and '05 - sell both needles
SKU: 5EL-1490J-20-00 - NEEDLE SET UR 49 UR 49
SKU: 5EL-1490J-00-00 - NEEDLE SET UR CA UR CA
Note: Stamped on the needles (not part number1):
-- US needles are 5DL 43-53-1.
-- Australian/Euro needles are 5DL 39-53-3/5 on carb 1 and 5DL
40-53-3/5 on carb 2.
Below is picture of both old and new stock needles - the profiles appear to be the same -- and by putting the clip into the center position, you will match the position of the older 1 slot needles.
Note: If there are more than 5 clip positions, it is not stock - most likel in from DynaJet kit.
Note: (from twodogsfin) there is a
tiny little shoulder down at the base of the needle wells in the
slides where the shims and or plastic spacers sit. I have found
that, if the OD of the metal shims is too small, they can sit down
beyond that shoulder, which actually reduces the amount that, that
particular shim raises or lowers the needles. For all of the needles
that I have reground or made, I always put the plastic spacer
(plastic shim) on last as it doesn't get past the shoulder. That way
I'm sure of where i'm at with needle height.
Staggered Jetting - Why Not? (or Why Do it)
(added 11/21/07)Stock bikes come with staggered jetting (different main jets for front and rear cylinders) and MaxAir recommends that same setup when you install their POD kit and reject.
Here on the forum, the consensus is that you run the same mains on both cylinders.
Why the difference?
Crumystar put it best:
Lots of different opinions on that one and I'm sure you'll hear them all. BG. Here's some of them....
-- stock air box is very restrictive and due to it's design and shape the front cylinder will get more air thus requiring more fuel
-- front cylinder will run cooler than the other due to it being out in direct airflow. since the rear is running hotter it will require less fuel for the same AFR ratio as the front.
-- stock exhaust cast elbow at the back of the head. it is more restrictive than the front elbow built into the pipes.
Personally... i think it's a combination of all three. However...--I've taken individual pipe AFR ratios with a pod kit and aftermarket pipes (which still used the cast elbow) and found them to be dead even.
-- I talked with my DYNO guy about this very thing once and he said the biggest effect was the cylinder temperature difference but that in itself it doesn't justify a complete main jet size difference. makes sense to me.
-- He said, if ANYTHING, maybe run about .003"- .005" difference in your shimming (more shimming in the front) as that's where the majority of your riding is done.
In the idle circuit you're not going very fast so air-flow isn't a big deal and on the average riding day you're hardly into the main jets. That's my $.02 anyway.
~nick
What Jets (Updated 12/114/08) BACK TO INDEX
When you need jets for the 1100's stock carbs, you are looking for:
Mikuni CV Carb Jets - Small Round Jets
Mikuni Part Numbers:
Mikuni Main Jets: KN102221-xxxx where xxxx is the jet size, i.e. 110
Mikuni Pilot Jets: KVM28/486-zzzz where zzzz is the jet size, i.e. 17.5
All Jetting Kits will advise/supply ones required, or a range that may be required.
Refer to tables above for best knowledge on what main and pilot jets work in what situation.
Sources:
Our own Metric Magic (TimB1007) via email metric.magic@gmail.com (preferred source)
Bernie @ Fox Distributing 630-513-9700
Bike Bandit: http://www.bikebandit.com/brand-nav/mikuni?d=2450434&o=1
First and Foremost - do NOT use Dyno-Jet (DJ) kits!
The reason why DJ jet kits are not recommended is they were poorly setup from the start for the 1100. They are hard to tune, and they cost $80. Most dealers use DJ jet kits when they re-jet because they would have no clue on how to rejet other wise, and in most cases they are sending bikes out not jetted correctly. So yes there is a history of bike having problems with the DJ kits. In addition, the DJ jet numbering scheme/sizing is totally different from the Mikuni jets which are the best to use on our Mikuni carbs.
Forum thread on the "badness "of DJ kits: http://forums.delphiforums.com/yamaha1100/messages?msg=22469.1
DynoJet to Mikuni Size Cross Reference
If you have these jets installed, back them out to go to PODS - see: Undoing Old Jetting (click)
BACK TO INDEX
(updated 07/04/08)Note: folks on the forum do not think much of this option - especially if you have any air mods - see the thread:
http://forums.delphiforums.com/yamaha1100/messages?msg=13808.1
How to spot and remove a DynoJet kit: (courtesy of cruzmystar)
The easiest way to tell is to look at the needles. DynoJet kits have multiple clip positions on the needles and stock needles do not. The main jets use a different numbering chart than Mikuni does. Dyno jet numbers are slightly lower than Mikuni's. This can potentially cause some problems because a 120 DJ main is much richer than a 120 Mikuni main for example, so be very carefull in keeping them seperated and labeled. It's pretty common for dealers to install a DJ kit when installing a set of pipes. Upon inspection you might find a 108 main in the front carb and a 112.5 in the back. At first this is confusing but the 108 is a DJ main and is one step larger than the 112.5 mikuni main. To remove a DynoJet Kit all you have to do is replace the main jets with Mikuni brand ones and remove/replace the needle assemblies. Stock needle assemblies can be purchased from your favorite yamaha dealer (Yes, TimB has them too!) and will come with all the spacers, shims, etc. to convert back.
Stock Needle:
Removing a Hypercharger/High-Five Air cleaner: (courtesy of cruzmystar)
Here's what you'll need to do in order to properly remove the components included in a Hypercharger jetting kit. The obvious part is the actual air cleaner and ducting itself but the changes to the carb are the key issues.Kuryakyn uses Mikuni brand main jets so just replace the main jets with the appropriate ones from your new air kit.
The needle assemblies will have one additional shim added to them from the stock configuration. If you're adding a POD kit to the bike then leave that additional shim in there as it's a pretty good starting point for most setups. If you're going back to stock then you'll need to remove one shim from under the white plastic spacer.
When installing a Hypercharger they want you to replace the factory Air Bleeds with the new ones included in the kit. From the info I've gathered on the forums it seems that about half the time this actually gets done. The factory Air bleeds can potentially be very stubborn to get out and can strip quite easily. A Hypercharger can be tuned to work without their air bleeds so a lot of people just don't mess with them. The air bleeds are located underneath the needle diaphragm in the carb. See reference #16 in the picture. Kuryakyn call theirs size 1.2 and Yamaha calls theirs 145 but i believe it's a 1.0. Stock air bleed part # is 1HX-14231-29-00. If you don't know or can't tell if they've been changed then I highly recommend changing them. This will absolutely need to be changed back to stock configuration when adding a POD kit or returning to stock or it will cause some very definite low-end tuning problems.
Final area to look at is the vent on the carbs. When installing a Hypercharger the provisions are given to extend the vent hose on the carb and attach it to the actual air cleaner. This is done to help combat some high-speed tuning problems the Hyper's have by equalizing the float chamber pressure with the intake charge. Even if you are leaving the actual Hyper air cleaner on there just for looks and adding a POD kit you need to REMOVE this vent hose from the air cleaner. If you don't you'll over fuel the carbs at higher speeds resulting in a very rich condition. In stock configuration the vent hose simply slips through a ring held down by a float bowl screw and ends shortly after that ring. Make sure there's a 45* cut on the end of the hose and leave it there. See included picture.
Next Step? - Drill Slide Holes, Shorten Slide Spring - Faster Carb Response
(updated 08/08/08)AGBack:Slide Hole Drill, Spring Clip??
The initial dialogue . . .
rosskp:
If the carbs are the same and the motors vastly different, might the threory and the practice still be applicable on the 1100's?
A guy named Ivan in europe that has put countless hours developing a jet kit and mods to the FZ1 carbs which are identical to ours, check it out! some interesting theories. www.ivansperformanceproducts.com
My point about Ivans theories pertaining to the carb setup and mods that he has done, including needles that have 5 angles in thier design -- can any of his modifications be relevant to our machines. I'm not suggesting that I was going to replace miy 1100 carbs with the FZ1 carbs. Not the case, just wanted to look into any and all possibilities that could help our bikes. I have sent an e-mail to Ivan to see what he thinks. Let you all know when he responds.
Yamaglide:
One of the things that Ivan does is drill out the holes in the carb slides.
When I dyno tuned my bike with Shane's 502 kit I went to Kendell Johnson's Customs . He builds a lot of custom bikes and Harley's and that is what he does to all of the bikes that has CV carbs and talked me into drilling one of the two holes in my slides. I drilled them and made another pull and it made a noticeable difference on the dyno ,
I stopped at one hole but have been thinking about drilling the other hole ,the worst that can happen is I would have to buy two new slides.
Most CV carb builders drill them out including the guy that made Shane's Pro needles that I run. I guess the point I am getting at is the things Ivan is doing with sport bike Carbs is the same thing we can do to our bikes and any other bike with a CV carb if you are trying to get every thing out of it without putting flat slides on it.
Drostar100:
Dynojet recommends that on all of their carb kits for the "stage 3" LEVEL.
I have done it on two in-line 4 bikes and seen no difference at all. Maybe its my elevation (way less vacuum up here) or maybe it doesn't make a difference until you go really extreme with the engine but I have had no luck with it. Never tried on a v-star.
Yamaglide:
Dynojet even includes the 1/8 drill bit with there kit. It was noticeable on my bike with the heads ported , its pumping a lot of air now. I am running a 162.5 and a 165 main now. Have you ever tried adjusting the springs?
Drostar100:
I haven't. Is that your next step?
rosskp:
I'm going try it tomorrow (I have an extra set of carbs ) and see what happens....let you know..
I am going to drill out the holes, and cut the springs down by 1/2" and see what happens. I have no cams, but bike screams, we will see.. I have all of the instructions from Ivan plus a forum member of the FZ1/R1 forum put together a pretty comprehensive set of instructions including pic.
I am going to start with 1/2" and see what that does. Ivan recommends 3/4" and both holes drilled out to 1/8", VERY, VERY IMPORTANT!!! DO NOT USE A POWER DRILL!! you can drill through 2 of the prongs that hold the needle holder.
Yamaglide:
I saw that when I drilled the one hole and turned the bit by hand to make sure I did not damage the prongs.
rosskp:
Ok, drilled out the holes on the slide to 1/8" and cut the springs to 4",
OMG what a difference! I rode it to my club meeting tonite, and could feel a vast difference.
Better response, smoother all the through the throttle range, and barely had to open the throttle at 70 mph and just a blip got me to 85 mph.
IMO I think this is something we should have done along time ago!! I believe that the slide being able to open easier helps throughout the power band. I would do this in a heart beat and highly recommend it to all. I am thinking of ordering Shanes needles to see what effect that has, couldn't hurt!!
- - - - - - - - - - - - - - - -
Expanded installation / modification instructions - Not for
1100's - just info
Here is a thread that explores the above - perhaps with a future
mods for many of us - once the "kinks" get smoothed out - Not ready
for endorsement, but maybe a next step in performance.
http://forums.delphiforums.com/yamaha1100/messages?msg=36114.1 (w/o HiJacs)
http://forums.delphiforums.com/yamaha1100/messages?msg=36103.1 (was HiJaced)
Troubleshooting Carb Problems (click link)
Synching Carburetors (updated 12/22//08) BACK TO INDEX
Note: Not only is this a procedure when you jet, it should be done each time you adjust the carbs, and anytime the bike starts to run roughly.
Note: Reminder for DIY Manometer: Turn the synch Screw Clockwise (in) to lower the oil level for the rear carb.
(Will make sense once you read the following articles)
SilverBack (AGBack):
Note: Before beginning this process, ensure the bike idle speed is set to 1000 rpm and the bike is warmed up. Note: Several of the forum experts indicate they set their idle higher for synch and then turn it back to 1000 when done. They use a variety of rpm from 1200 to 1500, the idea being to synch at a higher speed to represent the wide range of rpm the bike uses. Not sure if it is better, but that's what they do - no harm in trying.
The process whereby the two carburetors and their cylinders are synchronized (obvious from the name of the term) relative to the timing of throttle opening - so the throttle plates open at exactly the same time - making for balanced power - synchronization!
Turning the synch screw/bolt (picture below) which is located on the left side of the bike, behind the chrome carb cover and slightly ahead of the crabs toward the front of the bike adjusts a linkage between the operator's throttle mechanism and a link between the two carbs' throttle plates. Note - this process only requires very small movement of the synch bolt/screw -- never more than 3/4 turn AT THE MOST.
Synchronization of the throttle plates is measured by the vacuum created by each carb / cylinder immediately below the carb attachment to the cylinder. This is accomplished by attaching equal length vacuum hoses to the small port at the base of each carb (pictures to follow) - equal hose length and hose internal diameter is critical. The other end of each hose is attached to a measurement device - either a two or more line manometer (purchasable) or to the DIY manometer - recommended! - (see link below).
During the process, the bike will be running at idle, the synch screw will be turned very slowly (with 7mm wrench!! - screw driver is too clumsy!!), by turning the screw slowly in both directions you can ascertain the proper direction to make sure the two columns of measurement fluid in the manometer are at exactly the same height in the device - indicating the balance has been achieved in the vacuum in each cylinder, and therefore the throttle plates are opening at the same time - synchronization! Note, again - this process only requires very small movement of the synch bolt/screw -- never more than 3/4 turn AT THE MOST.
Damping the fast movement of the measurement liquid in the DIY manometer columns. - Vacuum line restrictors can be purchased in your auto parts store or, for performance modified bikes, insert the old / stock pilot jets into the hose ends of the manometer - far enough to allow insertion of the connector below the jet.
Once balance is achieved, blip the throttle once and let it fall back to idle, and then refine the balance as needed, if needed.
Synch Ports:
Stock bikes: Rear cylinder port has the AIS hose connected to it. Front cylinder port is capped and clipped. Disconnect the AIS hose at the port near the carb and uncap the front port at the carb -- then attach the synch hoses for the process described above. When done synching, remove the synch hoses and replace the AIS hose and the front cap and clip. (see next paragraph for alternative)
Performance enhanced bikes usually will have the AIS either disconnected or removed - to eliminate exhaust popping noise. If this is the case, it is suggested that you permanently install synch hoses (remember: equal length and ID), plug them (important) and store them out of sight on the bike when you are not actually synching. They can be stored: in the space emptied by the AIS pump removal, or in the empty dog bowl if you decide to keep it on the bike, or in the tool compartment, or just under the tank. It is suggested you store them in a location that allows access with minimal "part removal" for future access. Vacuum hose plugs can be found at most auto parts stores and can be used to plug the ends of the "stay in place" synch hoses.
Caution: If you decide to use the old AIS vacuum hose as one of your synch lines - be sure to remove the restrictor that is in place on that line - and be sure to make your other synch line the same length and ID!! If you do not do this - your synch will not be in synch! Best to run two new lines of equal length and the same diameter.
Connection from the synch hoses to the manometer. It is suggested you use a vacuum hose connector of the proper OD to fit the ID of both the synch hose and the manometer hose. If you use the 3/16 ID hose for the manometer, a simple connector is all that is needed to connect to 3/16 ID hoses installed on the nipples (and left in place), or the synch tool hose will fit directly over the nipples.
Pictures to Locate the ports and synch screw (click picture for larger version)
| Synch Screw Location | Front Cylinder Synch Port | Rear Cylinder Synch Port |
 |
 |
 |
Another Note: Many folks have cross connected the "manometer" ends of their synch lines. Extensive discussion has led us to the conclusion, that this practice does no harm, NOR does it do any good. It is NOT an automatic synch. It does NOT balance the vacuum across the 2 cylinders. It is NOT magic. See the discussion thread here: http://forums.delphiforums.com/yamaha1100/messages?msg=12688.1
Still Another Note: When you blip the throttle, you will note the cylinders fall out of synch and then fall back into synch. there is discussion underway on the forum about whether we should be synching at higher than idle - more like at the rpm level we cruise with. The jury is still our - no solid testing / proof - so synch at 1000 rpm - UNLESS you want to be a guinea pig and so some testing of synch at higher rpm. If so, start a thread on the forum and volunteer - there'll be a lot of folks with ideas and interest. See the above thread for some of this discussion, also.
Note: one of most respected wrenchers does his synch at 1200 -- then resets the idle lower. if you want to try this, let us know if it improves things.
Comment from Drostar:
don't over think it -- you set them in sync at idle so they work
together appropriately when you take off, when you first twist the throttle
you want both carbs to open at the appropriate time time, as you increase in
rpm they will not stay in sync because both intake valves are not opening at
the same time obviously and the more rpm you have the more the vacuum
changes and the valves open and close faster......same in a car with
multiple carbs, when you mash the gas pedal you want the carbs to open at
the same time not one and then the other....
Everybody puts way more emphasis on the carb sync than they need too - it is
not an exact thing and never will be at any rpm, you just want it as close
as possible.........they even give you an acceptable range of difference
between the two at idle........ don't over think it
---------------------------------------------------------------------
Daddo (DaddoCFL) (updated 1/23/06)
V-Star 1100 Carburetor Synchronization process
In order to properly synchronize the carburetors on your engine, your valves really needs to be set to their correct tolerances. And the engine idle speed should be set to it’s correct range. I keep mine right in the middle of the 950 to 1050 rpm suggested by Yamaha.
The manual suggests that the bike be placed on a suitable stand or lift. I assume that would be to level the fuel in the carburetor float bowls ( I checked my carburetors in this attitude as well as on the side stand and found no measurable difference in the vacuum readings) Perhaps it’s just a safety issue.
Ok, You will need to remove the Seats and Fuel Tank in this order:
1. ) Passenger Seat – Single Allen head bolt.
2. ) Seat Bracket – (not necessary on Classic.
3. ) Riders Seat – Single Allen head bolt on a Classic, the Custom’s seat was held on by the seat bracket
4. ) Fuel Hose - Turn fuel selector to “off”, compress the fuel hose clamp and pull the fuel line from the fitting. Keep a wipe rag under the line as some fuel will run out.
5. ) “Igniter plate” ( Spelled Ignitor in the manual) This assembly, with a rectangular electronic module on it is held on by three (3) “quick fasteners”. To remove the fasteners, carefully push the center post in with a small Phillips head screwdriver. Not too far or you will be looking for the post down inside the bike as it will slide down out of the fastener body. There is no need to remove it from the bike, but it must be loose to access the Speedometer lead connector. (to reinstall the fasteners, you must push the post back up through the body of the fastener until it extends far enough up from the fastener top to allow the body to compress. Insert the fastener into the hole and depress the post to where it is flush with the fastener body.
6. ) Mud Guard – The Igniter Plate was mounted to it on the Custom
7. ) Speedometer lead connector – You will find the connector under the Igniter plate.
8.) Remove the Fuel Tank. – Two bolts, on both the Custom and the Classic.
9. ) Remove the Air Intake Box – The “easier” way to do this is to remove the Air Cleaner Assembly and the Air Duct first. The Air Intake Box is held in place by a hose clamp on each Carburetor, another on the top end of the Air Duct, and another on the breather hose that comes out of the front cylinder head.
10. ) Remove the two vacuum plugs. Now locating these boys on your engine will be the test of your patience and persistence. The carburetor vacuum ports are on the ducts which leads from each carburetor into the cylinder head. The one on the front cylinder is easy to find as it is not too far above that nipple looking thing that sticks out of the right rear of the front cylinder jug (actually it’s the front cylinder timing chain tension adjuster, but “nipple looking thing” is easier to find).
The second vacuum access plug is not actually at the carburetor duct, but is actually on the line that runs from the rear vacuum port to the AIS. that hides in the storage compartment of your bike. Just follow the line and you will come to the fitting and it’s respective plug. Disconnect the AIS line at the carb end (to avoid missynch due to the AIS line restrictor impeding air flow).
(( Note: Added by SilverBack & Daddo - If you remove the air cleaner box and the left side chrome carb cover off - and you can access it all without removing the tank. But, removing the tank the first time will let you install permanent synch hoses to some readily accessible place (AIS spot / tool box spot / empty Air cleaner spot) , so future synchs will be faster.))
Measurement Process
1. ) Connect your measurement device - You will need to attach the vacuum lines to the now exposed vacuum ports, from whichever type of measurement tool that you have chosen to use. You may have to use adapters that came with your measuring devise depending on the type and size of the devices vacuum lines
This will work the same if you are using dial gauges, a mercury tube type gauge or a Morgan Carbtune. Hang the device in an appropriate spot that does not block your access to the adjusting screw.
The accuracy of your measurement is really dependant upon how well you follow the device manufacturers directions in damping the engine pulse on the vacuum lines going to the testing device that you are using. All directions will differ slightly but the goal here is to restrict the flow of air in the test lines to the point where the relative vacuum can stabilize, but the flow is so restricted that it will negate the violent pulsing of the indicator. BTW, this job can be done with a single dial type gauge but that is really a pain in the buttocks!
2. ) Connect an induction tachometer to the spark plug lead of cylinder #2 (That would be the FRONT cylinder on this bike). Note: Can also be connected to the rear cylinder - whatever is easies for you!)
3. ) Start the engine and let it warm up for a few minutes.
Now this is an issue for you to consider, and a choice for you to make. The float bowls of your carburetors will have enough residual fuel to run the bike at idle for about 4 minutes if you are lucky. This is more then sufficient time to sync the two carbs, but the engine must be HOT to get accurate readings.
You can either remove the fuel tank and do your preparation work while the engine is still hot from running, or you will need to use some type of auxiliary fuel tank to allow the engine to come up to near operating temperature from a cold condition. A lot of motorcycle supply houses sell small plastic remote fuel tanks that hold a liter or so of gas, or you can salvage a tank from a discarded lawn mower and use that as I did.
4. ) Synchronize carburetor #1 (rear) to carburetor #2 (front), by turning the synchronizing screw until both vacuum gages read the same. That screw can be found between the V and just under the carburetors. On the left side of your engine, you will find a chrome carburetor cover. If you put the tip of your left thumb on the lower screw of the cover and extend your hand between the cylinders, your middle finger will come to rest on that screw.
The difference between the two gauges should not be more then: 1.33kPa (10 mmHg).
And the reading at idle should approximate: 34.7 – 37.3 kPa (260 – 280mmHg)
(( Note: Added by Silverback - Daddo is talking about using either of two commercially available synch gauges which allow you to exactly measure the level of vacuum in the two cylinders. You can use the DIY synch gauge - referenced above and linked to below) - and still use his procedure - just ensure that the level of the fluid is the same on both sides of that gauge.))
5.) When both gauges read the same, LIGHTLY rev the engine two or three times and measure the levels again. (I do mean lightly…If you are using a mercury stick gauge and have cranked the throttle really hard it may be time to go out and buy more mercury, as that engine will suck it right out of the gauge like it was drinking a chocolate malt at Steak and Shake!)
Button it up! It’s a done deal! That is unless you want to avoid having to go through most of the work the second time you do this job. If so, keep reading.
Since one intake duct already has a hose connected to it that runs back to the AIS compartment, you simply need to run another hose from the nipple on the front carburetor duct back to the AIS compartment (That would be the duct that connects the carburetor to the head. it's not really correct to call it a manifold, and I am assuming that your AIS is still in place and you have not removed the rear vacuum line).
(Note: added by Silverback) - If you use the "former" AIS hose, you should remove the restrictor - to keep the line the same - ID and length - see article at the top of the topic)
After you accomplish this, you can sample the vacuum from each carb, right in the AIS compartment. You will need to stop at your local auto supply store and pick up enough same sized Nitrile vacuum hose to do the job. You will also need a vacuum line “T” as well as a couple of vacuum line plugs. Install the “T” in the existing vacuum line that actuates the AIS “pump”. Then plug the bottom of the “T”. In addition, you will need to plug the end of the new line that you have run. To sync your carbs, simply connect your gauge to the bottom of the “T” and the new line.
Less work for mother the next time you do this job. Nothing has to come apart any more.
--------------------------------------------------------
$1.55 DIY Carb Sync Tool by Marty Ignazito BACK TO INDEX
Alternate Links:
-- http://www.challengers101.com/Manometer.html (Stop after "Building the manometer")
-- http://650wiki.org/index.php/12.19._The_$1.55_Carb_Syncronizer
Note: Damping the fast movement of the measurement liquid in the DIY manometer columns:
- Vacuum line restrictors can be purchased in your auto parts store
- or, for performance modified bikes, insert the old / stock pilot jets into the hose ends of the manometer
- far enough to allow insertion of the connector below the jet.
Note: Damping the fast movement can also be accomplished via the use of heavier oil:
-- some use 90 Wt Gear Oil
-- others have suggested fork oil
Remember - the reason for using the 2-cycle oil is two fold: visible color,
AND IT WON'T HURT THE ENGINE IF SUCKED IN - MAKE SURE WHAT YOU USE MEETS BOTH CRITERIA.
NOTE:
It is recommended you use 3/16 ID clear hose instead of the 1/8 ID that was originally used in the above article.
Reasons:
a.) will cause less "bounce" when measuring/synching - larger ID means more fluid / weight to move therefore less "bounce",
b.) 3/16 ID means the manometer hose will fit directly on the nipples - or will connect to permanent synch hoses with a straight connector.
Either size will do the job, but 3/16 is better!
And, if you think you need to spend more than is really needed:
Another DIY Carb Synch Tool: http://faq.ninja250.org/wiki/How_do_I_synchronize_the_carburetors%3F#Carb_sync_tools
And even one more - two legs with gauges - http://forums.delphiforums.com/yamaha1100/messages?msg=49465.14 (Originally mentioned in the forum by gmcrkrjr)
Bench-top Synching: (Tim's approach, words by Cruzmystar)
With the carbs out of the bike hold them up to a light and look down the throats. Take a sewing needle or something of that sort and bring the idle screw down until the needle will barely slide underneath one butterfly (try and remember how many times you turn it so you can get it back to where it was when you're done). Then take the needle out and check the other butterfly. Adjust the synch screw to get both butterfly's where they are even. This will get you very close to synched. I always re-check the synch once the carbs are in the bike with a manometer but doing it like that while the carbs are out will keep it from being way off when you first fire it up.
Mercury vs. Oil - "Calibration" -- Thanks to JeffJ (jdjstar)
The ratio of mercury to oil is pretty easy to calculate. The density of mercury is 5.43gm/cc and the density of mineral oil is .835gm/cc. So the height of a column of oil that is equivalent to a column of mercury would be 5.43/.835 or 6.5 times larger.
A 1" column of oil is equivalent to a .15" column of mercury.
DaddoCFL :
The adjustment screw (actually bolt) is on the left side of the engine.
Place your left thumb on the lower mounting screw of the chrome carb cover and extend your hand under the tank. Your middle finger will rest on the adjusting bolt.
Although it is slotted for a screw driver, that is not going to happen. It is 7mm wrench that will do the job for you. Small degree turns will be the way to go while you watch the two columns of your dual column manometer equalize. If the imbalance gets worse, you are turning the wrong way.
Don’t forget to damp the pressure in the vacuum lines or the bouncing will drive you nuts trying to compare the levels.
Another Article: Jack Phelps - Carb Synch
When the parts Don't Fit - One Saga of Getting It To Synch (updated 9/15/06)
From: KroozerGuy (after a lot of forum help and a ton of stick-to-it-ive-ness)
Executive summary: Poor fitting detail parts did not allow the front cylinder carb butterfly to close as much as the rear cylinder carb butterfly. Linkage had to be adjusted so both butterflies allowed the equivalent amount of air flow at idle.
Excruciating detail: I have never been able to really sync the bike at idle since I've had it. The first time I tried, I made one of the $1.55 manometers, and almost pulled all the oil out of it. So I went to mercury and the density allowed me to at least see the vacuum differences and get close at idle and equal at higher rpm's. Since I could never sync at idle, I would sync at the higher rpm's. I could rationalize this by convincing myself that this is where I did most of my riding. I remember discussing my inability to sync and syncing at higher rpm with Dave Benson a few years ago on the ISRA forum. This was BMAK (Before MaxAir Kit). Everything seemed great and syncing at idle seemed to have little or no influence on performance, so I left things as they were.
Well after a few more years and a 18K miles, along comes the broken o-ring on the front cylinder PMS screw and all the associated repair and subsequent pod mods. With the help of you folks at this site and the ideas you suggested, I decided it's time to figure out why everyone else can use the $1.55 manometer and I can't.
If you read previous posts in this thread you'll see after the pod mod I had the idle adjusted side vacuum at over 300 mmHg while the sync side was somewhere around 160-170 mmHg. Changing the sync only caused the idle side pressure to decrease (320-330 mmHg). To check for vacuum leaks, I did the WD-40 thing around the intake boots and hooked the Hg sticks directly to the intake ports with no change in results. I also visually had looked at the butterflies while the carbs were installed. No indication that air was getting in to increase the pressure on the sync butterfly side.
Considering the possibility that I bent or misaligned things when removing the float bowl screws, I decided to take things off again and look at the alignment and poke around on the linkage to see if anything jumped out at me. Idle adjustment side (LHS) was left at the 300 mmHg or better setting and the sync side (RHS) was left where it created about 160 mmHg.
As soon as the carbs were removed I checked the butterfly openings by holding them up to the light, or back lighting them. On the idle adjusted side there was little to no light getting through, while on the sync adjusted side there was light coming through the bottom and some of the sides. The light gap was very small, and there was no way to see this with the carbs installed.
I then tried adjusting the sync screw and noticed how the RHS carb butterfly would move during the adjustment, and that the adjustment screw bottomed out before the butterfly would completely close. I took the sync screw out and removed the spring that pushed against the linkage that the sync screw adjusted. Wish I had a photo, but the sync screw has a spring around it and there is another spring that pushes against the adjustment linkage. With the screw and springs removed, I was able to get the RHS carb butterfly to completely close. I was able to produce little to no light like the LHS butterfly.
I measured the distance between the linkage with the butterfly closed and the length of a totally compressed push spring. It turned out that the push spring would be fully compressed and inhibit linkage movement before the butterfly would completely close. My caliper said I needed approx. an .030" additional gap between the linkages to keep the push spring from being totally compressed during sync adjustment.
That's not much, so I took the trusty vice grips and did some bending. I was able to give myself an additional .050" gap. I suppose that there may have been a better way to align the butterfly linkage, but it wasn't obvious to me at the time. I replaced the screw and springs, and then used the back light method to adjust the RHS butterfly until it looked like the LHS butterfly. Remember I didn't touch the position of the LHS or idle butterfly.
I put things back together and started it. Of course I needed to adjust the idle to keep it running. Those butterflies were pretty tight in there. After it warmed up, I attached the Hg sticks to my sync hoses run into the tool kit or old AIS area. Wow, surprisingly I was at or close to 260 mmHg on both cylinders at approx. 950 rpm. I was totally amazed. What a feeling. It felt like I just reached the summit of a mountain.
So the reason I was never able to sync at idle ever since I've had the bike is because of the sync adjustment linkage. I was always close, but never really synchronized. Since I bought the bike new, done all the maintenance on it, and only had the carbs off prior to this for pms cap drillout, I believe it came from the factory this way.
The other thing that I think is noteworthy is the significance we place on the carb sync. Mine has never been adjusted properly at idle since the day I owned it. It was adjusted at 1200 to 1500 rpm. I suspect that if I could have measured it at higher rpm's, it would have been very close to being in sync there also. Mine has done just fine for 18K miles without a perfect idle sync.
I think that makes sense. At low speeds or high vacuum conditions, a small change in butterfly position effects or allows a larger percentage of the idle air flow and will have a more significant effect on measured intake vacuum. Since the overall quantity of intake air at idle is small, butterfly differences are easily observed. While those same butterfly differences at higher rpm's may only produce insignificant changes or undetectable differences in air flow because the total quantity of air flow is so large.
I think Drostar said it best in the KB - Don't over think the carb sync.
Thanks to all for the great feedback. Now I'll need to get my $1.55 manometer out again and fill with oil, so I can super synchronize my carbs
Krooz
Adjust Floats (added 07/14/09) BACK TO INDEX
: Shop ManualChecking Float Height - "Clear tube method" - documented in the Shop Manual, free copy down loadable from the KB - see the documentations section for the link. Page 5-7 in the manual - located here
NOTE: Yamaha tool not required - use clear tube and measure the required distance above the "sight point" - which is the seam where the float bowl mates with the carb. (right rear seam & left front seam)
Do Not Do It unless there is a real need:Notes:
-- You have installed MaxAir Predator Pro Needles AND You have a Solenoid bike Max Modded
There are enough cases of negative results of this adjustment if you are using the stock needles to suggest you should NOT perform the float adjustment unless your bike exhibits performance problems.
Bottom line, this mod clearly ONLY applies to 06 and 07 and later Cat Converter bikes -- when you use the MaxAir Predator Pro needles, which have a richer profile across all the carb circuits.
It is equally clear that you should proceed with caution in all other cases (non-MaxAir Predator Pro needles), and NOT use this procedure until your bike exhibits some symptoms pointing to over rich situations, that cannot be cured by other means.
Here's a link to Mad Max's article / instructions to get the job done:
http://www.maxairengineering.com/images/floatlevel/CheckYourFloatLevel.htm
More Info / Instructions:
To do this the carburetors
have to be removed from the bike and the bowls removed from the
carburetors.
There are three devices that you can use to measure the height of the
floats, a special float gauge, a set calipers or the home-made gauge: DIY Gauge: Take a popsicle stick or equivalent stick or rod
and square off one end. Measure off a distance of 14mm or 0.55 inch from the
squared off end and make
a mark. Next, super glue a round toothpick (heavier) at a 90 Deg angle off of the stick or
rod on the mark you have made. You have just created a measuring gauge.
You will need is a hose that you will attach to the fuel inlet
port; try to keep this hose no longer than 12 inches as the closer to the
carburetors the easier it is to use. It is best to hold the carbs sideways.
The bracket that holds the small
chrome cover on the left side of the carbs can be clamped into a vise,
freeing both your hands for the next steps.
Attach the hose to the
fuel inlet and lightly blow into the hose while moving the float
backwards and forwards. Two things will happen. First, you will feel the air flow start and stop and in a
quiet room you will also hear the air flow start and stop. This is the
location where the the float closes the valve. Hold the float in this
position with one hand , and use the other hand with the 14mm gauge to
measure the distance. Where the floats have not been
previously adjusted, there will be a gap between where the float closes the
valve and where the gauge lines up with the crown of the float (more below). Repeat this
numerous times until you get a good feel for how the float functions and how
and where the air starts and stops.
Now the adjustment part.
Between the float lobes is a
shinny brass tab. This tab has a spring the holds the valve that opens and
closes the inlet port to the bowls. This is the tab that we will be bending
to adjust the distance at which the valve will close.
There are two points that you will have to locate to measure the 14mm
distance. The first is the peak of the float. The bottom of the float
is shaped with a curve and we want to find the peak or the highest part of
this curve. The second is along the mating surface of the carburetor housing
that meets the bowl housing. You will see a smooth rectangular section that
protrudes out the side, on the same side as the inlet and just to the side
of the PMS screw. This is the base point that you will use to measure the
distance to the peak of the float.
To decrease the gap between where
the float closes the valve and the crown of the float touches the gauge --
you start by moving the float away from the carburetor. Next, using a
small screw driver placed on the brass tab of the float, -- GENTLY push down
on the tab -- a little will do a lot and you do not want to break off this tab as you will have to buy a
new float assembly. You have just modified the distance that the float will
close.
Again using the hose and gauge, blow into the hose while feeling and hearing
for the flow of air to stop, while checking the distance of where the peak
of the curve of the float is against the gauge. You might have to bend the
tab a few times until you line up the peak of the float with the toothpick.
As a rule:
-- if you have a gap between the crown of the float and the gauge, you will have to push down on the tab to increase the distance,
-- and if you do NOT have such a
gap, you will have to pry up on the tab.
Once you have the carburetors assembled and installed on the bike you will
find that adjusting the PMS screws and idle speed has greater sensitivity
and don’t forget to sync the carburetors to each other.
A good picture of how/where to measure - and the popsicle tool - thanks to oldfrank.
More Comments / Hints:
Nighthawk005: I know how you feel but after I was talked through it the first time it all made sense. I went to Harbor Freight and bought a little slide rule (metric ) for 1.49. Take the carbs off. Remove bowls. Now here is what I was messing up. On the left side of carbs is the bracket Turn the carbs 90 degrees so that bracket is facing DOWN and set it on level surface. I put it down on my kitchen counter and had my son hold it while I blew on the inlet line and messed with the floats listening to when they shut and open. Then did the measurement with my slide rule real easy. Others make there own. I will send picture tonight of rule I have it on computer somewhere.
Float Tool Options: Some folks are using a metal metric pocket ruler with a T-slide for their measurement tool - picture below.
Other Performance Information BACK TO INDEX
AIS (Air Injection System) Plugging, Removal (updated 06/30/09) BACK TO INDEX
Discussion: The AIS injects air into the exhaust chambers as a means of burning excess fuel when the bike is decelerating. When fitting less restrictive pipes (slip-ons or full systems), the AIS will (or can be see more below) be the cause of a popping sound on deceleration, which many find annoying (and others not).
WARNING: DO NOT Remove or Plug the AIS system with bikes having catalytic converters still installed -- 05 Calif. and all 06 and later bikes. Doing so could cause a fire!!
Note: (for those who don't understand "still installed") -- They are still installed if you have the stock tail pieces of the OEM exhaust still installed. They are NOT "still installed" if you put on either slip-ons or a full after-market exhaust system!!!!
Catalytic converters are designed to clean up exhaust emissions by burning off any residual unburned hydrocarbons. In the process they become extremely hot. If there is a large amount of unburned fuel passing into the Cats, they will get hot enough to potentially cause anything flammable near them to catch fire. The AIS system allows oxygen rich air into the exhaust system at the outlet port in the cylinder head. This oxygen will support combustion of any unburnt gasses and consume the hydrocarbons before they make it to the Cats, thus helping to keep the temperature in the Cats down. Disabling the AIS and keeping the Cats is high risk for a fire.
Cat equipped bikes also have fuel cutoff solenoids in the carb float bowls. The purpose of the solenoid is to cut off the fuel supply a few hundred RPM prior to hitting the REV limiter. This is done so that a heavy shot of unburned fuel does not make its way into the Cats when the REV limiter cuts off ignition to 1 cylinder. By the time the REV limiter is activated, there is no fuel left in the main jet circuit to burn. In fact the REV limiter on a Cat equipped bike is several hundred RPM higher than the limiter on a non-Cat bike but the engine will run out of fuel at about the same RPM as a non-Cat bike, so if everything is working as it should, a Cat equipped bike will not actually hit the REV limiter. This is why people who have installed POD intake kits and modified the float bowls and solenoids are reporting a higher REV limit than the older bikes.
These components are designed to work as a team to clean up exhaust emissions, they should not be modified piecemeal. In order to remove the AIS and/or the solenoids it is prudent to also remove the Cats.
Much thanks to Daryl - WhiteStar246 - for this excellent explanation.
Note: There may be other causes of the popping on deceleration once you have added freer flowing exhaust - the idle may need to be raised, the carbs synched, and the PMS reset. So, before you do the AIS plug or removal, make a pass at being sure you have the bike well tuned, and then decide. Thanks to imnezrider (mdpar3) for challenging the "it's the AIS" theory and confirmation by Drostar (Drostar100) for this new insight.
-- So, one reason for disabling or removing the AIS is to get rid of the popping sound.
-- Also, many of us do not care for the chrome piping used to supply the air from the AIS pump, feeling it clutters the lines of the engine.
-- And, you gain some storage space when you remove the entire system (my bike alarm fit nicely in the hole.
AIS Removal / Plugging Article: PDF file -clck to open, right click to save
AIS Removal thread on the Forum: Excellent comments and links to other comments
NOTE: Downside of Quick & Easy method of AIS "Removal" - SilverBack (AGBack) reporting info from many threads on the forum.
This approach is only a stop-gap, and will require you to do a full AIS removal down the line - in a year or so. With the lines plugged, noxious gasses and fluids will collect in the pipe, eventually causing them to rust through and spew ugly looking gunk on your beautiful chrome. At that point, you will have to do the complete removal. (I know, did the quickie, and after about 2 years - did it the right way. Be warned! If you are experiencing popping exhaust on deceleration after going to free-er flowing pipes, then you should use the quickie method only to ensure you have pinned down the problem - and should do the full removal as soon as you can - or just set aside the extra time and do it right the first time.
AIS Plugs and Elbow Replacement - SilverBack (AGBack) reporting info from many threads on the forum.
Once you have removed the AIS per the above, you can install the bolts with "glue" as noted to plug the holes into each cylinder. At the time of the AIS removal instead of bolts and "glue", or later if you plugged the elbows with bolts and 'glue", you can opt to replace the elbows with better looking AIS Plugs for several sources - IF YOU WANT TO SPEND YOUR $$ ON SOMETHING THAT YOU HAVE TO STAND ON YOUR HEAD TO SEE. Each source provides you with instructions on how to remove the elbow and insert their AIS Plugs.
The big caution here is to work carefully, gently, with only enough force to get the job done. Folks have been know to damage cylinders by being overly forceful.
The basic technique for removing the elbows are to use a slide hammer with a hook attachment, or to use vise grips with a combination of rotation and pulling. The rear is fairly easy and accessible. - the front is more difficult.
From BioHazard (Vrated): The Poor Man’s (or thinking man’s) slide hammer. What I used to remove the AIS elbows was a pair of vice grips. I remove that adjustment bolt on the vice grips on the end of the handle and replaced it with an 8 inch long bolt. Clamped the vice grips to the AIS elbow, then using an pair of pliers loosely hold the end of the 8 inch bolt, then hit the pliers with a hammer. After a couple of good whacks that elbow came out. Took all of 5 minutes I did this for both AIS elbows.
Installing the plugs mirrors the removal of elbows for difficulty - rear is easy, front is difficult. For the rear, slip the plug over the long end of a large Allen key, and then tap it into place with a few taps of the hammer on the long axis of the Allen key - as it it were a nail. For the front, use the same key, but place the small end into the plug, and position the plug and the key so you can tap on the flat side of the key, slightly offset from where it is in the plug - to tap it in without hitting the frame riser. If the ones you buy have an installation bolt, you can do as noted above, just put the bolt in and use the right sized allen key to fit in the bolt head,
Frankly, when I looked at the location of the elbows - pretty much hidden out of sight, I decided to forgo spending the extra $$ and worrying about installing - I just used the bolts with "glue" approach recommended in the AIS Removal Article. Worked for me!
AIS Plugging - After Removal - 45 ACP Casings
(added 04/14/10)
Use 45 caliber ACP (Pistol) Casings - tap in gently, open end first into the AIS hole - NO GLUE / GOO needed
Find a Dyno Near You & Sniffer & Run Types (updated 09/30/09)
Dynos are the best means of determining the performance of your bike
Note: Make sure the Dyno you try can measure: Horsepower (HP), Torque (TQ) and Air-Fuel Ratio (AFR)
Note: See Section on Performance Comparison for added comments on dyno machines and HP.
Note: You can make two kinds of Dyno runs: (info from Vstar_in_NH - Jack Rosa)
-- Sweep - Throttle wide open during the whole run - Dyno records HP and TQ over the entire RPM range, as does the sniifer logging AFR
-- Step ---- Every 1000rpm the Dyno holds the bike at that RPM and you crank the throttle on through the range to see if it leans or goes rich, then it goes to the next step. 2k, run through the throttle circuit, 3k run through the throttle circuit, etc, etc.... This tells if your pilot, needle and main are transitioning correctly.
Tachs / Setting Idle 950-1050 rpm (updated 05/09/09) BACK TO INDEX
Setting Idle - need a Tach - see below.
The idle screw is reachable from the saddle. just below, behind and slightly to the rear of the triangular (sort of) chrome cover between the cylinders. Look for a black knurled knob attached to a shaft that goes up behind the chrome cover. Idle should be set when the bike is warm and between 950 and 1050 rpm.
"Tuning" Tachometers - Vendors / Comments
These are tachs that you hook up temporarily to set your idle or other wise use while tuning your bike
Discussion thread: http://forums.delphiforums.com/star_riders/messages?msg=81242.1
Mounted Tachometers - Vendors / Comments
These tachs are permanently mounted for viewing / using rpm's while riding.
NOTE - Best to connect to the right side coil - that one is NOT connected to the rev limiter - less interference.
Tachometer Alternative - TREYSIT Sirometer or Vibra Tach -
- http://www.treysit.com/TREYSIT_Sirometer__revolution-/treysit_sirometer__revolution-.html
- Briggs & Stratton sells this as their PN# 670156 and they range from $13.50 - $25
Interesting piece of gear - uses vibration to accurately measure engine rpm (accurate within 100-150 rpm - it is a resonating reed-style tachometer..
Sparkplug Guide / Info / Reading: http://www.totalmotorcycle.com/maintenance/sparkplugs.htm
and another, includes reading: http://www.nightrider.com/biketech/spkplghnbook.htm
Reading Plugs - NGK - http://www.ngksparkplugs.com/techinfo/spark_plugs/faq/faqread2.asp
Coils BACK TO INDEX
Coils are covered in the section on other Electrical - Click to go to the Coil Info
Cams (update 09/16/09) BACK TO INDEX
Types vs. Result (Performance) (updated 9/30/06)
Here's a thread to look at - a good "Here's What I Want -What About Cams
Thread ISRA Hardweld vs. Roller Cams
Still missing any information on the PCS cams.
CAMS vs. ORKs (updated 04/01/08)
See discussion under ORKs in OIL Section
Installation (updated 03/19/11)
Cam Instillation Process - Created by Joe Conway - joe91898(joeconway) - Edited by SilverBack
The instructions have
been: converted to a PDF file for downloading, and amended to be in
checklist format - making it easier to keep track of each step.
Click Here To Download Cam Instruction the File
Warning: There is a risk you might drop the 22 MM socket into the case when you revolve the engine! Suggest you do one of two things - your choice:
Buy a deep-well socket (22mm) - it will be long enoough to do the job and not fall into the engine
- better to be safe than sorry (as you will likely have to pull the engine and crack the case to get the dropped socket out!
Another Warning: you will need to readjust valves - so also look here: Adjusting Valves Instructions
424 Cam Install on 06 Bike (with info for all installers) - forum thread
Cam Break-In Thread From the Form
Vendors (updated 03/09/07) BACK TO INDEX
Comments from Shane on their cams:
The SS-420 and SS-424 cams develop the same HP and TQ (significantly over stock cams), just in different parts of the RPM band
The SS-420 cam is a mild street grind designed to improve mid-range and top end power. They are for use with the stock pistons only.
The SS-424 cam is a mild street grind designed to improve low end to mid-range power band. They are for use with the stock pistons only.
The SS-502 and SS-580 cams are performance cams requiring different pistons and other changes
The SS-502 cam is a hot grind designed for street race applications. It requires HC pistons and should be combined with our standard bore 95mm 11.1 pistons or our 97mm 11.1 pistons. This kit, with SS Pro-Pipe yields 95,5 HP and 76.2 TQ (per Shane's Dyno sheets0.
The SS-580 cams are designed for 97mm bore race applications. They require that a minimum of 12.1 compression be used
More from SS web site:
Stock Cams: -- Average bike equipped with an
air kit, drag pipes and Dyna.
Max HP range 58 to 63
Max TQ range 56 to 60
40 to 45 ftlb of TQ achieved by 2500 RPM
Average Max TQ carried from 3000 rpms to 4500 rpms
Standard 420 performance kit - Average bike equipped with cams, air kit,
drag pipes and Dyna.
Our 420 cams are a great all purpose street & highway cam. Designed to
work with the bikes stock pistons this cam grind offers great mid range
and upper end power. The cams kick in at about 3500 RPMs and give you
what feels to be endless power right to the rev limit. The way the power
is distributed with this grind it's almost like adding an extra gear to
the bike. Perfect for highway use.
Max HP range 70 to 75
Max TQ range 65 to 69
50 ftlb of TQ achieved by 3000
Average Max TQ carried from 4500 to 6000
424 Street Racer cams -- bike equipped with cams, air kit, drag pipes
and Dyna.
Now if your looking to hot rod around town, this cam grind is for you.
Let me tell ya what,...These cams can crack the whip for sure!! Our new
424 cam grind has awesome low end grunt, way better than stock and offer
great mid-range power too. This grind also makes a nice change in the
1100's exhaust note as well...These babies thump...
Max HP 70 to 75
Max TQ 61 to 65
50 ftlb of TQ achieved by 2300 RPMs
Max TQ carried from 4500 RPMs 6000 RPMs
Note: Special Carb Tuning Instructions for these cams is is the Jetting 101 Section.
PacificCoastStar (PCS) - See their site for information - let us know what you experience with the application of their cams
PCS Cam Performance Information - Ed (twodogsfing) has promised to document his experience with the PCS xxx2 Cams - with configuration, tuning anf performance information. Once that arrives (waiting since Mid may 2009) then I will post it here.
Ignition Electronics (updated 02/24/09) BACK TO INDEX
Discussion:
One discussion on the forum indicated that the Dyna ignition module had little, if any benefit unless you had added cams in addition to air intake and exhaust mods. Some Quotes:
-- "There's really no good performance reason for upping the rev limit because the stock system already allows you to rev higher than the peak of the torque and horsepower curves. If you do mods which move those curves higher into the rpm band you might gain some performance, but with your current setup thy extra revs will get you little or no real-world performance gains."
-- "The biggest advantage of the Dyna on a mostly stock bike is the ability to adjust the rev limiter." (see note above)
This is a grey area for me, so have at it and let me know what's up here. These boxes provide plug and play replacement for the stock ignition, and then provide you with multiple performance curves, multiple rev limit settings.
When looking at sources for Dyna, I cam across a rating on Cruiser Customizing, indicating that the Dyna module was a cheaper way to replace a failed stock module that getting a stock module from Yamaha. So, take a look to see if this may be true for you if your stock ignition module fails.
Caution: '05 California and all '06 and later Models
- as
of 01/06 Dyna says they do NOT have a module for your bike - might have it
in 6 months! (Still waiting!)
Note: 02/09 - Dyna has just come out with a model for the newer 1100s - 05 (Cali) and up (all states)
Vendors:
Note: 02/09 - Dyna has just come out with a model for the newer 1100s - 05 (Cali) and up (all states)
Dyna Performance Dyna 2000 (Less costly! Same, except lacks ability to retard timing for NOS or turbo/blower)
Dyna C Curves & Discussions (updated 09.26.07)
What Ignition Curves to Use - Discussion And another discussion thread.
There is an on-going discussion about whether to disconnect the TPS (Throttle Position Sensor) when using the Dyna Ignition module. Dyna says to keep it connected as the TPS provinces advance during the lower rpm range. Some folks have found that disconnecting the TPS (at the wiring harness plug!) has helped with a hanging idle problems and others with excessive kickback.
Shane, SS Custom Cycles, says to run with it disconnected if you have internal mods like cams or pistons installed.
Also appears that running curve 6 is providing "seat of the pants" ore power and definitely smoother running - again for cammed or piston modified bikes..
DynaTek Curve Chart showing advance
supplied by TPS when connected with the Dyna.
(click to enlarge)
Coils - see topic in Section 8 - Coils
Wind vs Bogging Engine (updated 07/14/10) BACK TO INDEX
Problem:
I recently had a weird problem on a gusty wind ride. When I was riding into or away from the wind, my 1100 Classic ran fine but when I was in the heavy cross winds (sometimes leaning into it) the engine started cutting out. (I have a MaxAir kit.) Could the wind blowing across the pods/carbs have effected performance ... and more important...how to avoid it without staying home on windy days?
Tuck the offending hose up under the tank so it
does not hang down - use zip tie to hold it there.
Original (but no longer
preferred) Solution: (see alternate
solution below)
STEVEN3202: It's the vent tube,
cut it at a 45 degree angle facing forward, should take care of it, lots of
posts on the max air garage about this venturi effect on the vent tube.
bdc1964 said: I tried this quick
fix (cutting the vent tube at 45 degrees) and it works better than rerouting
the line. I went riding today in 20-30 mph winds and took the bike up to
110mph. Didn't cut out once. The vent tube starts at the top rear of the
carb assy and hangs down to the right side of the bike as viewed by the
rider (the rear brake pedal side). I used a razor blade to cut a 45 deg
angle on the tip of the vent tube and pointed it with the open part facing
forward.
Troubleshooting Carb Problems (updated 12/27/08)
Carb Cleaning - See This Article
Carb Rebuild Kits:
Keyster - http://www.keyster.jp/index_e.htm
Per Road Bike: wide range for japanese bikes, excellent prices
Mikuni Carb Tuning Guide - http://www.mikuni.com/fs-tuning_guide.html
From Cobb on the forum:
All right guys, listen up. If I've said it once, I've said it a thousand times: Trying to diagnose a jetting or problem based on engine rpm is a waste of time.
Here's why: When you tell me or any other tech that the bike farts and burps at 3000 rpm, we've no way of knowing what circuit the carburetor is using at the time. As you can appreciate, 3000 rpm in fifth gear is a very different throttle opening from 3000 rpm in first gear. Even if you fill in the blank spots, the best anyone can do is guess which fuel circuit you're using when the problem occurs. And, if the problem is with carburetion, knowing which fuel circuit you are primarily using when it occurs is essential to correct the problem.
To make an accurate assessment of any carburetion problem, you need to know where the throttle is positioned, indicating which fuel delivery circuit is in use when things go haywire.
Trying to figure out where your throttle is while dodging traffic can get a little hectic, so try using this simple tool next time you've got jetting issues. Wrap a piece of masking tape around the throttle housing. On the tape, mark the closed position, wide open throttle, and the points in between, where the throttle is 1/4 open, 1/2 and so on. With the throttle closed (that is, released and at rest), stick a colored pushpin in the grip, adjacent to the Closed mark. Now, using your indexed markings, note the point on the throttle where the problem occurs. This will let you (or at least the tech) determine which carburetor circuit is primary when the problem occurs.
Once you know which fuel circuit is affected, solving your problem should prove much easier. Plagiarized from the Melbourne Star Riders Forum
More:
MITCHELGUITA:
To give you a better understanding of how the carbs affect the way a
bike runs you really have to break down how a bike runs into four
different categories:
1) idle to quarter throttle 2) quarter to half throttle 3)
half to three quarter throttle 4) three quarter to wide open
throttle
1) idle to quarter throttle:
The questions here would be how does the bike idle, do you have proper
sensitivity with the PMS screws and is the transition from idle to
quarter throttle smooth.
2) quarter to half throttle:
The questions here would be is there a hesitation, do you has a smooth
transition, do you get a cough from either the intake or exhaust, or
does it seem to lack power. If it stumbles, can you hold the throttle at
the position where it stumbles and it will continue to stumble (too
rich) or if you hold the throttle in that position where it stumble and
it goes away by itself (too lean).
3) Half to three quarter throttle:
The question here would be the same as 2.
4) Three quarter throttle:
The questions here would be the same as 2 but with the addition of top
speed.
With these definitions you will be able to describe in clearer terms what is going on so that it will be easier to focus in on the problem area. There are just too many variables too address without them.
