Idle WAY too high and gas Leaking out of the right air box?!?! Help!

domdom

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What is going on? My bike starts up great, only right away it jumps up to about 7000 rpms and feels like it's going to climb. It's nothing wrong with the throttle cable, tested that it it is just how it should be. Not with the idle adjustment. I've had that thing tightened and loosened to both extremes with no difference. I sat down to ponder on my predicament and then noticed gas leaking out of the right air flow box. Not the left, the right one. What do you guys think? Floats? Wiring? Cables? Global Warming? Terrorists? To me, at this point it could be either, hah.

Thanks a bunch

Dom
 
Floats-check them. Adjust to 26-27.5mm above the gasket mating surface. Make sure there is no schmutz on the needle seat and that the needle and seat are in good condition.
 
Gas leaking is as mentioned either the float level is off, or most likely the needle, and seat.

The high idle could be a lot of things.

You're gonna have the carbs off to check the floats anyway, so might as well tear the carbs down completely and check everything.

Carbs synced?
Diaphragms in good shape?
Everything that should move, moves freely?
No clogged jets? (including the needle jet)
No cracks, or other leaks in carb boots?
O-rings in good shape? (including the one on the air screw)
 
I've never done carbs before, this will be an adventure. Thanks a lot guys

Dom
 
The carb on a 250 cc scoot I had a few years ago did the same thing. I stopped at the P.O. and came back out to smell gas and find raw gas leaking out the carb bowl overflow hose. P
Got the scoot home and pulled the carb, opened it up, cleaned and thoroughly inspected everything. Did not find one speck of dirt. Put it back together and the scoot ran perfectly. Still no leakage for the new owner after 4 yrs. Most likely the float valve stuck open.

While the carbs are off, it would be a good time to check/replace the idle mix screw o-rings as well as the choke rod seals. You can get both from Mikesxs. Both can be sources of air (vacuum) leaks. Wouldn't hurt to replace both float needle valves, too. I prefer to do these kinds of things when I have parts off the bike and can do them at my home with proper tools instead of on the side of the road somewhere.
 
Mine is an '80 so the carbs are different. I am not as familiar with your carb type but Drewpy said your year/model does not have the o-rings under the idle mix screws. Not certain about the choke rod seals, either. Look up your year and model and you should be able to find out which carb or others here who know can help.

BTW, spent 31 yrs. in the classroom teaching H.S. Bio.
 
Oliver, ebola, and turek, thanks a lot. I think I'm going to get a carb rebuild kit and get to work on it ASAP. I've got the idle a bit lower, but its super gummy. Pretty sure this should do it for me. I'll keep you posted (litererally, haha).

OliverB - Bio?! That's great! I'm PE (but doing quite a few different subjects at the moment..you know how it is)
 
A rebuild can't hurt anything, certainly, but do you know you need one? If it were me, I'd clean them way, way too much and adjust everything and see if anything is actually worn out before i bought anything...but I'm cheap. Good luck!
 
Quick update, the carb rebuild kits are on their way and un the mean time, the float screws were adjusted to lower the idle. I'm not running it, just working on the body right now.
 
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