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Discussion Starter #1
So here's the story, I have an 06 V-star 1100. This spring I went to start it up and it only ran on one cylinder. I pulled the tank off, got to the airbox and noticed gas backing up into it, bingo, bad carb. I had a lot going on that month so I took it into the Dealer for a carb rebuild job. I was told it would be a few weeks cuz they're backed up, no biggie. Couple weeks later they call, all done, come pick it up. I go in, pay 330.00 (ouch!) and they bring the bike around. I can tell immediately that it sounds different, sort of flat? I have aftermarket slip-ons on it. I get on it and start riding away, bad news, runs like poop, leaning out all over. I turn around take it back, they look at it and tear it down to adjust the mixture. An hour later he says "here try it now, take it around for a bit" I drive around and its no better. So back to the Dealer we go. I leave it with them overnight, they call an say i've git bad intake boots. They did the brake cleaner spray test and it dropped idle. So a week later they get the boots, tell me its ready. I go in and pay 220 (ouch again). The mechanic brings the bike up and says "I must've had these carbs off 6 or 7 times. Its still leaning out a little in high rpm but it must be because of the pipes" i drive away and WOW!! It still runs like garbage, not as bad as before but still bad. I can't believe they let me drive this away. So i thought screw it, i'll do it myself. I tore the carbs off. He had 110 jets fir both carbs. I put a 112.5 one in the front. He also only had the mixture screws out 2 turns. I turned them out 3-1/2. And it still leans out bad in mid and high throttle. Any ideas? I'm at a loss here.
 

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https://sites.google.com/site/vstar1100kb/home/tuning/carb-jetting when it comes to jetting i check the table, scroll down about a third of the page to table a. and compare the bikes setup .slipons with stock exhaust.
a test to check a lean condition is when your having a problem is slowly open the choke to see if the condition gets better or worse.
 

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What are the needles set at? Are they stock needles or did somebody put in dynojet stuff? (as in jets and needles)?

I'd make sure they are stock Mikuni jets and needles. Dyno jets sizing is different...and their needles aren't the best.

Did you tyr the choke test Nick57 mentioned to verify you are lean and not rich?
 

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Discussion Starter #5
I will try the choke test tonight. Not sure what needles they changed, if any. Guess i will have to take them off the bike and dig deeper to find out. Is there a way to tell if the needles are mikuni or not?
 

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Discussion Starter #7
Tried the choke test, it didn't make it better at all. I guess I'll pull the carbs again and look at the needle jets. I should also back the pms back to 2 turns.
 

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the brass colored phillips screw i dont think it has a purpose..maybe they use these carbs for other vehicles..with slip-ons you could go up to 115 on the mains, also with slip-ons you may get popping on decell. if so opening the pms screw out an eighth turn at a time till the popping goes away. if you get the mains and pms set like in the kb and you still have issues i would take a look at what type needle is in it definatly would be best a mikuni.
 

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Discussion Starter #10
I don't get any poppin on deceleration. I have the pms turned out to 3-1/4 right now and it's going lean on 1/2 - 3/4 throttle. I'm going post of video of it tomorrow going down the road, then I'll pull the carbs off and look at the needle jet to see what they got in there. I'm SO asking for some of my 550.00 back from the dealer when I get this running right.
 

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Discussion Starter #12
Yep, sorry, I meant just the needle. I haven't done anything with the needle jet, I'm assuming they left that alone. Like I said, I'll post a video, maybe you guys can diagnose this better than me. But I swear it is "leaning out" at mid and high throttle.
 

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Discussion Starter #13
Here's a video I recorded by putting my iphone in my pocket and going on a ride. You can hear the engine cutting out. Is this the fuel getting lean or does it sound electrical? Either way, I still can't believe the shop gave the bike to me like this and called it good. Here is the youtube link.
 

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sorry i dont know.i put blu tape on throttle housing and marked closed one quarter ,half ,three quarter and full with a sharpie. then you will know at which throttle position it starts to break up. and knowing the position you will know which carb circuit is fouling up. it sounded like quarter to half which would be pilot jet and needle, maybe getting into the main.
also on startup you get a lot of kickback you should check the tps it can cause starter clutch failure very expensive.
 

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Discussion Starter #17
OK, I'll look into that. Other issue first. I guess I'll start by pulling the carbs off again on my next day off and checking out the needles. The cutting out seems to happen between 1/4 and 3/4 throttle, which suggests the needles. Do you think that changing the main jets from 112.5 front, 110 rear to 115s would make that big of a difference?
 

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i dont think the mains would make that big of a difference you seem to be loosing one cylinder pretty drastic, its probably just the pilot jet clogged, use a bread tie wire to clean the side holes of the jets.
at the end of the kb you can download a service manual chapter 5 on the tps. or else a clymers same thing.
 

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Yah, I don't like the way it starts at all.. I know that is currently the least of your worries, but something's not right there..

In regards to your other issue, I can hear it missing in the very beginning while you're idling, and then on up through the range.. Let me re-read your posts and I'll come back with my thoughts..
 

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Ok.. Just curious.. Have you checked any of the voltage levels? My 93' Vulcan would act like this when my battery was headed south for the winter.. It's worth a look. If all of your voltages check out at least you know you're looking at a fuel problem. Do what Nick said and double check all of your passages. I wouldn't change the jets, I think what you've got now is fine. I'm running 115/112.5 but I have a full exhaust.

GL!

eGo
 
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