This 4 wheeler starts and runs good the only problem I have found is that when you have it opened up and running fast and when you let off the throttle it backfires one time and it does it every time you go fast. It runs fine at medium speeds. Does anyone know what could cause this?

Thanks,

Daylon

 

Most of the time it is a lean idle mixture but also could be an exhaust leak. Check your exhaust doughnut gaskets, they do wear out.