Two Stroke Motocross
Two Stroke Motocross Forum => Technical => Topic started by: cnrcpla on March 14, 2012, 01:58:57 AM
-
I know, usually it goes the other way around with two stroke about idling. But I just did my top end, and the idle is WAY up there. It isn't an air leak between the carb and the reeds, because the motor isn't racing up, just a high idle. I did turn the idle adjust almost all the way in, with little affect. Just curious, maybe it will go away after I finish breaking the motor in.
-
Check and make sure your throttle cable isnt out of adjustment or sticking. It could have too much tension on it causing it to be on the gas a little.
-
I did. No tension. I reved it a few times, and I would think that if the throttle was stuck it would have stayed, or taken a while to go back down to normal idle speed. But it doesn't feel any different and there are no visible pinches or binds.
-
My mate with a KX500 had a leak from between the case halves, and it ended up seizing. Don't rule out something like air sucking through a seal.
-
Check the cable is seated properly in the top of the carb. when you open the throttle and let it snap shut you should be able to hear the slide hit the bottom. if you can't your cables not seated somewhere.
-
Ok, I will try that. And how can I test for an air leak between the cases?
-
with the bike idling spray starting fluid around seam between the cases and with the flywheel cover off spray around the shaft.
the rpm will go up if you have a leak.
-
I was just about to update. I took it for another break in ride today and it seemed like the idling is going down as the engine becomes broken in. I also think I figured out why. I couldn't help but notice some exhaust gasses sneaking out the engine and head pipe. The O ring slipped out in a few places when I re assembled and I think that's been causing my idling issue. I'm going to put that back in place and let you guys know how it worked tomorrow.
-
maybe thats the problem .
but also if it won`t idle down or use long time. you may have to adjust the air/fuel mix screw ritcher..
-
GOT IT
With the exhaust leak and a small but noticeable air leak between the carb and reeds... I'm disappointed I didn't notice it. The clamp was on tight, but something happened that prevented a good seal. All set now, thanks for the help guys 
-
GOT IT With the exhaust leak and a small but noticeable air leak between the carb and reeds... I'm disappointed I didn't notice it. The clamp was on tight, but something happened that prevented a good seal. All set now, thanks for the help guys
what do u mean exhaust leak? like the gasket/o-ring was messed up?? when i was looking at my bike when it was running with a high idle there was some exhaust smoke coming out from where the cylinder and exhaust pipe meet. 
-
Yeah. the O ring was over stretched and it had a wavey kind of look, so it was not sealing everything properly. The small leak wouldn't really cause a racing idle, it was just something that CAN cause it, but in my case it was the air leak. If you still couldn't pin point your racing idle, and you already checked the carb slide was seating properly, then make sure there is no air leak between the carb and the reed block, and the reed block and the engine. Make sure all your clamps are on tight, everything is all nice and sealed and not sucking air. If all this checks out, then worse case check your crank seal on the stator side. If that seal is worn or slipped out, then that could also race the idle.
-
ya i got it fixed
-
Nice man, have fun riding it