Help! First ATV project here. I purchased a partially disassemble ATV, put it back together and I finally got the engine to run and it runs great. The problem is that when it put it into gear it barely moves and stutters or jumps. The best way I can describe it is if you have a driver/drill with a clutch, if you put the clutch on light and hold the chuck then run the drill, that is the sound it makes and the way it lurches. If I put it in reverse and drive slowly, it will move in reverse. Is this something in the transmission or the differentials? Just trying to figure out where to start looking. Any thoughts are appreciated.