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Discussion Starter #1
I have a vstar 650 2006 ,12k miles. Towards end of summer last year was running great , was on a cruise at 60 mph and all of sudden lost power. Could barely get it home . It will start up and idle , as long as chokes on. I try to rev and it sputters and stalls. So i went thru replaced spark plugs (which were black ) fuel pump , fuel filter ,took carbs apart and cleaned ,replaced with stock jets (im only owner and bike was never modified ) still same problem. Tested coil was in the normal range , tested compression but only had a tester with rubber end u hold in spark plug hole ,both cylinders are 125+. Im kinda at a loss at would it could still be ,any ideas?
 

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Check the rubber between carb and engine. They are know to crack with age and heat. When they leak air it messes the air to fuel ratio which may be why it only runs with choke is on. One way I have checked for air leaks in the past (not the safest way but sure is easy): spray some brake cleaner or carb cleaner around carb area, if RPMs increase you have an air leak. The safe way, spray water, If RPMs drop you have an air leak. Good luck and keep us posted.
 

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all the ducts have to be air tight, once my air box slipped out of the joint at the top of the carbs and the bike ran bad, when i pulled the tank to check things i found the box had popped up off the front carb, main jets rarely clog it's usually the pilot jet that gum up because they have real tiny holes in them, there easy to remove and clean, i believe the pilot needle is plastic so be real careful with it, never tighten it down to hard if resetting it. and don't over tighten any of clamps on the ducts or you'll deform the rubber creating a leak
 

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I have had trouble with the airbox (intake silencer, specifically) coming off the carbs. It's a pain to get it on for good. Tightening the clamps just seems to push the rubber up off the carbs. Anyone have a secret?
 

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Discussion Starter #5
I checked the elbows between carb and cylinders ,sprayed with brake cleaner and didn't change how it ran , anyone know if tps could cause any issues like this ?and is there a way to test it. Seems like my issue is happening the same on both cylinders leading me to believe it could be another issue besides carbs.
 

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I checked the elbows between carb and cylinders ,sprayed with brake cleaner and didn't change how it ran , anyone know if tps could cause any issues like this ?and is there a way to test it. Seems like my issue is happening the same on both cylinders leading me to believe it could be another issue besides carbs.
you said it ran good on choke which means it's a fuel problem, ohms test the pick up coil it's the only thing that ever failed on my 650.
 

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I have had trouble with the airbox (intake silencer, specifically) coming off the carbs. It's a pain to get it on for good. Tightening the clamps just seems to push the rubber up off the carbs. Anyone have a secret?
tie it down with a few pull ties put together, just go right around the carbs and the box, tie it right in the middle between the two carbs
 
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