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Carb problems

It is possible that the rubber manifold seals (3) have dried out from sitting. There's one at each head, and the one the carb presses into. Since the carb was recently removed for rebuilding, look at that one first. It's easily torn when reassembling. There are various ways to check for air leaks, I prefer to wave an unlit propane torch at joints, but carb cleaner, WD40, even water works on SOME leaks.
 
I got a manual thanks for asking. I removed the carb and intake. I cleaned the mating surface on the cylinders and greased the seals and put it back together. I have it adjusted at 2 turns out from seat and it backfires out the exhaust and won't idle without the idle screw being all most all the way down. The one thing I noticed was the carb seal isn't very tight, it is new but the carb slides on and off very easily. Shoud the seal between the carb and intake be a very snug fit? I was thinking the seal from the carb to the intake might not be good. The bike revs higher when i spray carb cleaner around the outside of the intake. Is carb cleaner a good test for a leak or is the carb cleaner being suck into the AF?
 
Great catch Breeze. Something that needs to be looked at, but I had completely overlooked.
 
I got a manual thanks for asking. I removed the carb and intake. I cleaned the mating surface on the cylinders and greased the seals and put it back together. I have it adjusted at 2 turns out from seat and it backfires out the exhaust and won't idle without the idle screw being all most all the way down. The one thing I noticed was the carb seal isn't very tight, it is new but the carb slides on and off very easily. Shoud the seal between the carb and intake be a very snug fit? I was thinking the seal from the carb to the intake might not be good. The bike revs higher when i spray carb cleaner around the outside of the intake. Is carb cleaner a good test for a leak or is the carb cleaner being suck into the AF?

I think you may have found the problem. That should be a tight fit.
 
Carb should be a tight fit on to the manifold so perhaps you are drawing some air there and that could account for your current issues

Brian
 
Hey, partial success. I put the old seal back on and it was a very snug fit. The bikes idles and the backfires are gone. A couple of carb farts and the idle isn't quite right. I will get a new carb to intake seal as soon as possible.

When i rev the bike it is slow to return to idle. I will try to adjust the mixture using the idle drop method later this afternoon, then a test drive.

I will keep you posted.

Thanks for all the help...
 
Just got back from a 25 mile ride. The bike runs ok, not great. It still farts out the carb during the first 5 miles, warming up I guess.

I should have the new manifold seal by this weekend.

Thanks for the help...
 
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