Problems with idle speed.

Try adjusting the throttle speed screw, left side of the carb. You will want to turn it counter clockwise. If that doesn't do it, try the cable adjuster at the top of the carb. Screw it in unitl there is just a perceptable amount of free play between the cable housing and cable adjuster.

If that isn't working, then you probably have an air leak in the intake, and that needs to be fixed asap before you burn up your engine.

More commonly referred to, as the idle adjustment screw

I had the same problem, I loosened the throttle cable at the throttle and removed any sharp bends to the cable to prevent acceleration when the steering turns. After loosening the throttle I used the fine adjustments to fix the looseness.

Then I adjusted the idle screw on the carburetor to keep the engine idle low, but high enough to keep the engine running.