Hissing out of left carb and then bike dies.

Sweatybuns901

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Here’s my dilemma. Just recently got my
Bike all put together motor rebuilt by limeys bike shop in Austin TX. Bike fires up and runs but after it gets warmed up, say 10 or 15 minutes into the ride if I slow down to a stop say at a red light or stop sign my left carb will hiss like a backfire out the carb and the bike dies…. It starts right back up with one good kick. It’s only out of the left carb. Any thoughts/suggestions would be greatly appreciated. It’s a 82” xs650 converted to hardtail, Hugh’s hand built stator, regulator/rectifier from tcbros.
 

jpdevol

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I'd check the valve lash - esp left intake - and check the intake manifolds for air leaks (best guess at the moment)
 

Sweatybuns901

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I will do both of those! I’d hate to think it is my lash valves considering the top end was just rebuilt And my carbs and manifolds are brand new from HOOSracing but I’ll check those as well. Thanks for the suggestions!
 

jpdevol

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One of my suspicions, given your description, is the intake valve is too tight. That can sometimes happen on a fresh motor after a few runs.

What ignition is in it?
 

Jim

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Given' just one guess, I'd pick on the left intake valve also. And if you're not doing the work yourself, have 'em retorque the head after a thousand miles or so...
 

Jim

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Just noticed... you title says right carb. Your description in the first comment says left?
 

Wingedwheel

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If you’re a novice to working on these bikes the basics are not that hard. There are plenty of resources and info in the tech section and there are links to factory manuals which explain everything in detail. Yes left, sitting on the bike.
 
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