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Discussion Starter #1
I'm stumped. I've been working on a 71 CL350, (the 4th bike I've done), and it starts right up, starter or one kick.
The issue is, when I 1st got it it would idle up by itself. The idle stops are coming back to home, throttle cables are not stuck.
The previous owner said he cleaned the carbs, so, I got a couple rebuild kits and went through them properly.

It's better, as it doesn't rev up on it's own, but it is very slow to come back to idle. When shifting, in the time it takes to shift, the engine stays up.
If I pull the clutch in, it eventually, about 4-5 seconds, comes back down to idle.
The rubber is all good, so there are no air leaks.

I've never seen this before. I'm hoping someone has had this problem and solved it.

Thanks for any help and suggestions.


Premium Member
2,998 Posts
Lot's of things can cause this condition.

Advance Unit & Weights that are rusty/gummed up and not moving freely to return to the normal position.

Vacuum air leaks at the rubber carb insulator mounts (small cracks in the old hard rubber) - Replace if bad.

Air leaks at the throttle shaft where the felt washer have dried out or are missing. Often overlooked during a rebuild of the carbs. If you just dunk the entire body without removing the throttle shafts the cleaning solution will dry out the felts washer/Seals on the shafts causing a behind the throttle plate air leak.

Throttle Cables/Carbs not correctly sync'd

Points/Timing not dead on.

Try spraying some carb cleaner around the rubber mounting boots and at the throttle shafts to see if there is any change in RPM. If there is you have air leaks. and fix them first.

Then start looking at the advance with a timing light - does it advance to full advanced position (at approx. 3500 RPM) - then drop back to normal as the RPM's drop or does it stick?
If it sticks pull off the points breaker plate and Inspect, Clean, & Lubricate.

Do a valve adjustment check and timing chain tensioner adjustment.

All this stuff is normal general maintenance that has to be done with some regular intervals.
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