Originally Posted by
johndriver
Wildcat
The motor is a 17.5.
you will want the 12.5 rotor for roar. That is more of an onroad rotor. Both will work for 1s and 2s. as far as the 12.5mm rotor not fitting, you might need to shim it. If you dont know how, I would run the 12.3mm rotor until you can get some help.
also, the stock rotor should have the number 956 on the shaft