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Discussion Starter #1
2004 VStar 1100; Initial problem was bike starts then stops immediately. After trying Sea Foam, etc, pulled carbs and cleaned and rejetted (for upgraded exhaust). Rear main jet was completely clogged, seat was completely clogged also. Cleaned all seats, installed new jets, installed new parts from carb rebuild kit. Also replaced fuel filter and spark plugs. It started up great, but had fuel leak from fuel cutoff valve. Replaced valve and verified it works in both on/reserve. After sitting for a couple of weeks it went downhill fast. Now it will start for a few seconds then stop with full choke on. Intermittently it will start and can give it throttle, but when going back to idle stops immediately. When turning on initially, hear fuel pump run for about a second. The only improvement from before cleaning carbs is that rejetting cleared up popping when letting off throttle.
 

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you only pull the choke all the way out to start it

as soon as it starts push it in about half way - these bikes will not run very long with the choke on full

I hate to ask the obvious question: did you drain out the fuel in the tank, flush it out with a bit of seafoam, and fill it with fresh gas and some carb cleaner?

if there is still bad gas in the tank, after you clean the carbs they will suck in the bad gas again.

was the bike running well when you parked it, or did you get this bike in its present condition?
 

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Another thought, what is you ambient temperature? My 1100 never liked any choke above 80 degrees. What do the plugs look like? Even if new, could be fuel fouled with issues you are having.
 

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Discussion Starter #4
Completely cleaned tank out when I changed fuel valve. Temp was in the 70-80 range. Before I worked on carbs it would not idle (choke off). Bike sat while I was overseas. After carb work, and adjusting PMS screw and idle, it was idling with choke off. Sat for a couple of weeks before I could get back to it for final tweaks. But now just starts and dies with full choke. Will not start at all with choke at half or off. Battery is on tender so has a full charge. Have not pulled plugs yet. Plan is to check plugs, compression, fuel pump, and see where that leads.
 

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also make sure your air filter and intake are both all intact, and not plugged

and the exhaust as well
 

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Discussion Starter #6
First, thanks for all the input.
Installed new air filter - no change.
Replaced plugs when I rebuilt carbs. Pulled #2 (front) and good blue spark. Had black carbon build up on plug. Compression was 130. Replaced with new plug.

Pulled #1 (rear) and noticed it looked brand new. Spark was yellow, and took a couple of cranks of starter to get that. Compression 130.

When I had #1 out and grounded (for spark test), bike fired up and ran until I cut it off. Put new plug back in #1, and both with plug wire connected/disconnected bike wouldn’t start, with starter sounding bogged down.

Going to troubleshoot components of #1 electrical, but any idea why it starts with #1 out, but not with it installed?
 

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From what you described that cylinder jumped timing. I've never heard of an 1100 to jump timing except when engine was rotated backwards. Use your manual to check timing.
 
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