The Hyper 10 SC comes with a 12t pinion included Mod 1 to fit a 3mm shaft, for a VXL I'd use a 14-16t pinion range. To give you an example I am running a 3300kv Medusa with an 18t pinion geared for around 40mph on 2s Lipo and motor temps are yet to exceed 110f, with no heatsink or fan etc.