This motor in a mtb ?

[BrianG]

By the time that is geared down enough to limit speeds to a reasonable level (~15:1 @ 48v), the torque will be enough to rip the back end apart (even with torque arms) and twist your spokes into pretzels. If you can draw 250A from 48v, geared roughly for 40mph, that would be 176.09ft-lbs of torque at the axle.

Besides, that motor has a no-load current of 13A? Seems a bit high (inefficient) to me even for that size motor.

I would just get a hub motor. Less mechanical things to fab, cheaper, simpler, and cleaner looking.

[EDIT] Actually, one of the comments for that motor said the no-load current at 44v was 22A. Wow, that's bad. Almost 1,000w wasted power.