How exactly are people getting long run-times?

[Marvin]

It's definately free, there's no binding, and when my rotor failed on Sunday, I took the complete centre diff out (with motor still attached) and I was able to spin the spur/pinion combination like a clutch bell with those really nice 'almost failed' bearings that spin really freely.

I just thought that the tracks we race on in the UK aren't anywhere near as smooth as in the US, and also we have fewer jumps, which don't take that much throttle in comparison to sweeping corners, so presumeably the run time will be less anyway.