I just bought a 91 Banshee that wasn't running. I replaced the
cdi box and rebuilt the top end. I've had it for about a month and got it started for the first time last night. It sounded great, except for the fact that it wanted to rev to the moon when I didn't even touch the throttle. I had to hit the kill switch so I wouldn't sieze the new motor. The throttle cable wasn't stuck and moved freely. It has a one carb settup Keihin ( I think prev. owner told me 38MM) It is slightly tilted. The back of the carb is about 1/2 inch higher than the front. How do I fix this. PS idle screw on chike didn't help.

 

A free rev like that is more than likely an air leak somewhere in the intake between the carb and the cylinder... check the carb boot, it could also be a crank seal. If you can get it to idle with out free revving, spray some carb cleaner on the motor in the potential areas, and you will notice a change in the motor idle. Also check that the slide is not sticking in the carb