Stripping the gear? I had one rear gear set that I noticed after practice for a big two day race, which had one tooth 90% gone on the ring gear and two more teeth half gone an a 1/3 of a tooth gone on the pinion (not motor pinion). No one had a gear set within 100 miles so I shimed it up and it lasted the entire weekend and a couple of club races. My buddy put in 3 set of rear gears in his ZX5 within one full battery pack. I don't know what that was about.