[fred cook]

Disconnect the throttle linkage at the airbox lever and make certain that the throttle is closing completely. If not, there are two places on the throttle linkage where you can adjust the throttle rods (3 if you count the end by the throttle pedal). The rod gong up to the air box lever is the easiest one to access, but there is another shorter rod down on the throttle console mounted on the engine. If everything is adjusted properly the idle screw should be slightly open.