Hey, I was talking to Orion the other week. I ask some info on the core. the motor runs hot. cause it uses mod mags. inside. So don't worry about it getting hot like most monster and other out there. It is also a torquy motor to me I was running between a 27 and 29 pinion on our track which is med tight. I can't remember the spur size ( still the stock one) I was runnig red springs and reedy 767 brushes. hope this helps. my MI2 is asleep for the winter. we're in 12 scale mod here. and my Mi2 is on display at a chiro doctors office. with a body with there logo on it.