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Discussion Starter #1
ok, so i have a 99 xvs-1100 v-star custom. I have modified the factory exhaust. Rear baffle has been removed and the forward 2 have been drilled full of holes. So very little back pressure. I have removed the factory intake and have installed pods. Removed the ais system. I am having trouble Jetting the carbs. I have synchronized them and adjusted the valves. I have 17.5 pilots, 150 mains, 3 turns out on pms screw. 3 washers under the needle as well. the rear cylinder takes awhile to catch when its cold. Both cylinders have 130 ish psi of compression. I do not know if this is lean or rich. It pops through the intake sometimes. it did exhaust pop on decel untill i turned the pms screw out slightly. My has a batwing, hard bags and a trunk. my last tank i got 30mpg, but i was driving "spirited" and checking top speed. Which was higher than before. I also do not believe it has aftermarket cams. Any help is appreciated. will answer any questions yous guys have. Thanks.
 

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Just to clarify what is the pms screw you refer to.

The cold start problem may be the idle jets being blocked. A good dose of carb cleaner may solve this. As for the popping any mod on the exhaust...esp baffle removal will almost always cause some of that. It isnt a good idea to run with straight through pipes...most of the silencing is to appease authorities but a degree of it is to provide good exhaust flow.

You should get some idea of how rich the motor is running by doing a plug chop. The needles being raised by three washers seems a bit extreme. As for the mains and other jets it would be wise to find out what the specs are and if necessary doing small changes from those.

good luck
 

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Discussion Starter #3
i think its called a pms screw. it adjusts fuel throughout the whole throttle range. The exhaust still has some restriction. I had drilled the pipes before the rejet and it ran fine.(although it was a tad on the rich side) only rejetting because of the intake change and ais removal. I suppose i may have dislodged something in the fuel line and it plugged something. there is many idle circuits on these carbs. It only does it when cold. i have removed one spacer from the needle. each is 2 thou thick. the kit i purchased recommended 22.5 pilots, 150 front 147.5 rear mains, and 4 shims. The rear cylinder did not want to ignite at idle. and was blowing black smoke. the flames were cool though. so i dropped 2 in pilots and it helped. im a nube at jetting. (can you tell) so you recommend a plug chop? How exactly do i go about doing this.
Just to clarify what is the pms screw you refer to.

The cold start problem may be the idle jets being blocked. A good dose of carb cleaner may solve this. As for the popping any mod on the exhaust...esp baffle removal will almost always cause some of that. It isnt a good idea to run with straight through pipes...most of the silencing is to appease authorities but a degree of it is to provide good exhaust flow.

You should get some idea of how rich the motor is running by doing a plug chop. The needles being raised by three washers seems a bit extreme. As for the mains and other jets it would be wise to find out what the specs are and if necessary doing small changes from those.

good luck
 

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https://sites.google.com/site/vstar1100kb/home/new-owner-must-do-list read this must do list. never give it throttle when starting.. and check the mid shaft nut it sometimes comes loose and can lock the rear wheel.. there are sections on tuning and jettings. everything you need to know about the 1100 is here.two shims with pods.17.5 or 20 pilot jets 3 turns out on the screws and you can turn them out until the decell popping stops. in the jetting section there is a chart which tells about how to jet for pods and pipe mods.
 

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A plug chop is where you ride the bike at moderate speed for around ten to fifteen minutes. Pull in the clutch and cut the ignition then coast to a stop with the clutch pulled in. This gives an indication of the fuel getting into the engine at mid throttle settings without any slowing down through the gears and thus lower throttle settings.
 

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Discussion Starter #8
well turns out i was lean at idle and way rich at wot.
 

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i have full cobra exhaust, 3 and a quarter on the screws.if i let the bike sit for an hour after a ride sometimes i'll get a pop thru the carbs. 20 pilots but some guys in the past couple years are running 17.5..mine have been in for about five years and no complaints. two shims 0.05 total,150 on the front and rear mains. k&n pods.my plugs are almost white ethinol burns clean so i backed the screws out until i got a little color.
 

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Discussion Starter #10
i have full cobra exhaust, 3 and a quarter on the screws.if i let the bike sit for an hour after a ride sometimes i'll get a pop thru the carbs. 20 pilots but some guys in the past couple years are running 17.5..mine have been in for about five years and no complaints. two shims 0.05 total,150 on the front and rear mains. k&n pods.my plugs are almost white ethinol burns clean so i backed the screws out until i got a little color.
mine still pops through the carb sometimes. im running 20 pilots, 147.5 front and 145 rear. 2.5 out on screw. i was trying to figure out what shims were stock on it. it had a thick white one, a small silver and a really thin white one when i pulled it apart. so it had been messed with. i dont want to do too much till the temp comes up. if its on the lean side while its cold, it should ritchen up when the temp is in the 80s. its in the 40s now. what do you get for mileage?
 

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https://sites.google.com/site/vstar1100kb/home/tuning/carb-jetting if you scroll down there's a picture showing a needle with two shims below the plastic spacer. stock it comes with one shim when you go to pods you add one shim for a total of two. your pilot can be 17.5 or 20 people are running both. your lean on the screws you should be at 3 turns or more.. i'm getting about 45 mpg.i switch from reserve anywhere from 130 to 155.
 

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Discussion Starter #12
https://sites.google.com/site/vstar1100kb/home/tuning/carb-jetting if you scroll down there's a picture showing a needle with two shims below the plastic spacer. stock it comes with one shim when you go to pods you add one shim for a total of two. your pilot can be 17.5 or 20 people are running both. your lean on the screws you should be at 3 turns or more.. i'm getting about 45 mpg.i switch from reserve anywhere from 130 to 155.
so you have a 17.5 pilot? So i still have 3 shims on the needle. is your mpg at 65mph? or you running slower?
 

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i have 20 pilots, i run two lane blacktop.60,65.rolling hills,4th gear most of the time,4,000 rpm. if i go on the interstate i'll keep it at 70,75.
 

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Discussion Starter #14
Wel i got 40 mpg on my last trip. was 80 miles hwy, and 40 in town. before i was switching to reserve about 118 miles. now im in the process of making tru duals for it. will be loud (no mufflers) till i get my drag pipes.
i have 20 pilots, i run two lane blacktop.60,65.rolling hills,4th gear most of the time,4,000 rpm. if i go on the interstate i'll keep it at 70,75.
 

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if someone messed with it they may have changed the needles if so it will be hard to tune it easily. with mikuni needles the jetting is written done if you have dyno needles you will have to try to match the jets and settings to each circuit by seeing how it runs.
 

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Discussion Starter #18
if someone messed with it they may have changed the needles if so it will be hard to tune it easily. with mikuni needles the jetting is written done if you have dyno needles you will have to try to match the jets and settings to each circuit by seeing how it runs.
yeah and i dont know how to check if it is the factory needle or not. it only had the one c clip on it. but it seems to run alright. if only people would tell you what was done to it. The slide had 2 holes punched into it. the pms screws had no covers, the main jets had been changed, and there was another shim under the needle. so i have no doubt it was messed with. if only you were closer, id pay you to tune it. the bike shop here wants an arm, leg, and a testicle to do any work. $240 an hour.
 

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everything you need info wise is in the jetting section of the lincs.....17.5 or 20 pilots.. depending on the exhaust, weather modified or full performance the mains are 147 for modified and 150 for full performance.. two shims total they mic to .05. i'm not a machinist so i don't know if it's tenths or hundreds. the info is in the linc and there's a picture of the needle and washers.the pms screws should be 3 to 3.5. i'm not sure about the needle you have but i think if it's a dyno needle the bike would run pretty bad. and when you turn the screws all the way in you should feel the tip protruding into the venturi, make sure the threads are not bunged..... you can get needles from partzilla for $18.00 each or jets r us. be sure to get pre 2003 they';re easier to use.the problem might be needles or pilot error,..... i've been tuning (sincing) a 650 suzuki all week so go over and over your work
 
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