82 XJ650 running problems

My project bike is at the stage where Im attempting to get it running. I had a couple setbacks along the way. But this is what Ive done so far.

Carbs were disassembled and cleaned.
Benchsync'ed using the paperclip method.
Mixture screws were set at 2-3/4 turns out from bottom. (found this setting here)

The slides passed the clunk test and the throttle butterflys snap back with no problems.

I managed to get the bike to idle today, but it would only do so with the petcock on the prime setting. Then as soon as I touch the throttle it revved up and would not come back down even though the butterflys returned.

Should I buy a petcock rebuild kit? in hopes this fixes my petcock problem or could it simply be a vacuum problem?

And I dont really now what to make of the raised RPMs that wont drop. Even after I stopped the motor, I restarted it and the RPMs were still up at where they were when I killed it.

Sidenote: The bike has pods and open headers, I could see how this would cause running problems (even though when it was idling it idled fine) but not the revving or vacuum issue.

 

Yes rebuild your petcock. That is not why its hanging revs.
I suspect you have an air leak.

 

+1 - you can test the petcock by seeing if the fuel will flow if you suck on the vacuum tube gently - be sure it is not leaking gas through the vacuum tube first

 

If you suspect the vacuum hose from petcock to intake manifold you can just pinch the hose closed and see if that changes the hanging revs. No need to disconnect anything or risk ingesting gasoline.

 

yep. rebuild petcock .. and did you do a propane torch test on the cracked carb boots ?

 

More info on this propane test?

 

While the bike is running, take an unlit propane torch and probe around the boots, throttle shafts the whole intake in general.
If the rpm's in your motor rise you now there is a air leak were you are probing.

 

yea, its a super easy way to test your cracked carb boots. I did it the other day ... looks like the RTV inside the boots trick worked.

 

hey dood. Did you do this?

enrichment ckt cleaning