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Discussion Starter #1
First Off, Hello!

I recently bought a '76 CJ360T. It's only got 4000 Miles on it and runs pretty good...kinda.

Idles fine, Drives fine, the only problem I am running into is the RPM's Rev, and stay, high. Until I come to a complete stop and snap the throttle, then they'll back down. My neighbor, who used to work on bikes a while back, thinks it may be the vacuum piston on one, or both of the carbs. He says they could be ripped, or sticking. Is this a possibility? Could it be anything else? I looked into synching the carbs, but it doesn't seem to have the same mechanism as the older CB's, so not sure if they even can be adjusted in that manner. Haven't had a chance to take the top's off the carbs yet to inspect, but I figured I'd ask incase there's something else to look for.

Any help, or insight, in the matter would be greatly appreciated.

Thank You!
 

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Could be worn springs on the advance unit. Under the points plate on the left of the engine head is the advance unit. It has two little springs that attach to two little bob-weights. The bob-weights should snap back to centre if you lift them with your finger. If they dont return completely to the camshaft your idle will creep up due to the timing going to full-advance instead of full-retard when at idle.

Tell me..when you sit at idle (in gear) and the revs are high, does letting the clutch out a little bring the revs down?

Also...you may have a blocked slow jet?
 

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Discussion Starter #3
Yea, letting the clutch out will bring the revs down, usually it's the only way I can! I will check the timing cover, I never thought it could be that, just assumed the carb.
 

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Not the timing cover, points cover...the one above the left spark plug.
 

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Discussion Starter #5
Yea, that's what I meant. Sorry, it was late...I'm going to check the springs when I get home today.

Thank you!
 

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Discussion Starter #6
Springs are OK! I don't think it's the slow jet either, because it starts on the first kick, even the first half kick. I think I'm gonna pull the tops off my carbs on my next day off (Wednesday), and check for some cracks, can't think of anything else...
 

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I think your friend is correct....Sticking (varnished slides) ....you probably should clean the carbs.....While some slides are not polished looking, they should look clean and metallic everywhere....Any yellow or brown staining is dried fuel that can cause "sticking".... Be careful NOT to get carb cleaner on the rubber diaphragm...
 

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Discussion Starter #8
Well, took the tops off the carbs today, and sure enough, there's a tear in the diagphram right by the white O-Ring on the piston sleeve. Guess I need me some new Vacuum pistons! Anybody have suggestions where to get them?

Thanks!
 

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Bike Bandit still shows them available from Honda . . .for $85.00 each!!
You can temporarily patch them with Ultra Black Permatex.
Mine has been running that way for a couple weeks.
 
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