Since the Chinese gearbox on my Honda clone engine broke on my first ride. I'm considering just putting a clutch on the shaft and going from there with an alternative drive train (to the chainring). I want to do away with the gearbox completely. Is there a clutch with sprocket that will fit these Hua Sheng 4 strokes, similar to the easily available mini bike and go kart clutches? The engine shaft isn't the standard size like 5/8" or 3/4". The gearbox had a clutch but no sprocket. The gears in the gearbox didn't even fit together.