carb to boot leak

[stoneattic]

Has anyone had a problem getting the carbs to seal to the boots? I just got done rebuilding/cleaning the carbs and now when it warms up if I hit the throttle the RPMs stay at around 3-400 and won't come down. This only happens after it's run for about 5-10 minutes. If I spray carb cleaner around the carb to boot connection the RPMs jump up, leading me to think vacuum leak. I've tightened the clamp as much as I can and retightened after it warmed up, still no luck.

[Redbaron]

Carb pre-synch in order

Look through the forum, this is a common occourence after rebuilds. The carbs must be pre-synched to attain proper idle. Not sure if you did this or not. Search for carb pre-synch and follow instructions, if the butterflys are set too close the engine will suck air anywhere it can. HTH

[stoneattic]

Wow, thanks for the quick reply!

I did set the butterflys all the same before reinstalling the carbs using a bread twist tie as a feller gauge (I saw that somewhere on the forum). The really weird thing is that if I don't rev it at all after starting it, the idle will stay around 1200 (or where ever I set it). And the problem doesn't start until it warms up.

[Jeff]

Mine did this and I found that one of the carb boot clamps was scuffing the throttle linkage. It only did it after the bike had warmed up and I guess the boot and clamp had expanded just enough to make it scrub. With the folding pivot in the throttle linkage.... it still allowed the throttle to return to full stop. I noticed it after running the bike for a while..... and having the rpms at idle climb to 3-4k. After getting off the bike..... I began to loosen the clamps to pull the carbs. As I started to loosen one of the clamps... I noticed a very slight shift in the throttle linkage. I reassembled the clamps making sure that the screw portion of the clamp was shifted well away from the throttle linkage and I haven't had the problem since.