I'm just touching WOT. I may be getting into it too fast, but I only have so much range. This one broke at 70 mph. I'm starting to think some of the issues are the "pinion-on-pinion" setup I'm running. I might have to try going back to a plastic spur and metal pinion. Right now, I am running mod 1 gears (21/25). Maybe the small diameter and big teeth are causing too much vibration or something.