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Discussion Starter #1
I have a 04 vstar 1100 it runs great when the rpms get up but at idle front cylinder misfires and sometimes it will cut off completely rev it up a few times it comes back really hard to start have to give it throttle most times to get it started with or without the choke had the carbs cleaned the valves adjusted wont idle until it is at normal temperature
 

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If the problem is intermittent it sounds like an ignition issue, which can be hard to debug until the weak component fails competely

what do the plugs look like?

would also look for a vacuum leak on the front carb, boots, intake plumbing...

after the carbs were cleaned were they synched (balanced) ?
 

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Discussion Starter #3
Yes they were synced when I had the carbs cleaned could the coil for the front cylinder have a weak spark and cause that ?
 

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Discussion Starter #4
In the spark plugs look normal front and rear cylinder look the same
 

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https://sites.google.com/site/vstar1100kb/home/new-owner-must-do-list never give it throttle when starting. the tps advances the timing and causes the engine to kickback. kickback will strip the starter clutch, about a $700.00 repair. also don't stab the start button press firmly for ten seconds and let go. it sounds like your pilot jets are dirty the best thing is to take the carb apart and clean.. you can try a carb cleaner like berrymans b12 since it runs, it might work.
 

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I've taken the carbs off a month or so ago and I cleaned the pilot jet really good did not seem to really help much
 

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Discussion Starter #7
And even if it was the pilot jet would that cause a misfire?
 

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I had the same problem at around 5000 miles. I switched the plugs around and the problem switched cylinders. Bingo, changed plugs and all was fine. Hard to believe a plug would go at such low mileage.
 

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Any carb cleaner that you add to the fuel is worth the $8 for a bottle, it wont hurt anything, will clean your entire fuel system, and there is a good chance it will clean out the cause of a misfire.

When you had the carbs cleaned, what was the reason? Had the bike sat for a while and the fuel in the tank went bad? If so did you drain the tank, change the fuel filter, flush out the fuel pump? If not, the old gummy fuel will be sucked into your nicely cleaned carbs.

the ignition is definitely suspect - there is an in-line spark measuring/detecting adapter you can put in series with the plug that will tell you if you have a weak spark. It could be the plug, the wire, or the coil. For a quick check look where the primary side of the coil is connected (to the frame maybe).. if the connection is corroded it will make the spark intermittent.
 

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Something I have happen on my 02 1100 is the vacuum cap on the sync port will pop off, usually after getting a little too excited on the twisty noise maker. It runs great until I slow down. Pops and acts like it is cutting out from running lean...add a little throttle and it gets better, get up to a steady highway speed and it does fine. I ended up putting a zip tie around the vacuum cap to keep it from popping off. Not a solution per se, but definitely a get by.
 

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^ thats a good case history for a vacuum leak on the front intake causing the same problem, running far too lean at idle speeds

have you tried the propane (un-lit) torch test around the bottom of the carbs and boots? with the bike idling you point the propane flow around any area that could have a vacuum leak, and if the idle speeds up you found one.

Could also be a failure or leak in the AIS system, which has tubes and hoses pretty far from the carbs (where you normally would not look for a vacuum leak).
 
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