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2002 Vstar 1100 only running on the front cylinder. I am trying to bring it back to life after it sat for a few years. The rear cylinder has 155 psi compression and it appears to be sparking ok. See below video of spark gap of rear cylinder when the front cylinder is running. Also, I think it is getting fuel because the spark plug appears to have fuel on it when I pull it. I also put fuel directly on the tip of the plug and tried to start it with the front plug wire removed and it didnt sound at all like it was about to start. My next step will be to get new spark plugs. Any ideas on what else to troubleshoot?

Spark Gap of rear cylinder:

https://youtu.be/ebpqeTDJSP0
 

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If you have compression and good spark, that only leaves fuel and timing.

The fuel mixture has to be correct to fire. The cylinder could be flooded or too lean.

The timing could be way off on the cylinder.

One other thought, the exhaust for that cylinder could be totally blocked. There could be a dead mouse in the tailpipe (stranger things have happened when a bike is parked for years). The animal, not the DJ.
 

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I'd start by changing plugs.....but....if the bike sat for a while, the pilot jet could be plugged in the carb on the non-firing cylinder. That's what you need for start and idle.
 

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Carbs 8/

Carb issues are the culprit if you have spark, compression and air.

A stuck float will flood the cylinder, you will not fire and you will have fuel diluting your oil.

A clogged jet will starve the cylinder, and it will be too lean to fire.

The fix is a good carb cleaning, if you can take the bowl off you can test the float and make sure it seats properly when in the closed position, vinegar / water at a low temp boil will clean brass jets like brand new.

A way to keep this from happening again is to run Marvel Mystery oil or TCW3 two stroke oil (1 ounce per 5 gallons) in your gas . this lubricates / cleans entire fuel system and keeps gas from going bad, lubricates intake valve, and top piston ring.
 

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Also if you have access to it ethanol free gas endures the test of time much better then ethanoled gas. And if you can run it all the time your carb will be much happier.
 
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