Huh? I've been running the 8.5 for about 3 months now with no issues.I run it in a Rustler with the VXL,on 3s,Geared 18/87 with mashers it does about 50.But what makes it good is that it seems to run much cooler then the VXL motor.The important thing is to make sure it has the sintered rotor and keep it under 70000 rpm's going by there ratings.