Knocking noise from geared grunt hub motor

[flip_normal]

Bought a geared front hub motor from China and got it spinning using this controller.
As the no load speed increases (I haven't put it on a rim yet) there is a mechanical knocking noise coming from it (at lower RPMs it turns smoothly). The vendor claims I'm using the wrong controller. Has anyone else had this issue or is this just a defective motor? Thanks, in advance, any help is much appreciated.

 

[Chalo]

It could be a goober in the ring gear that bumps noiselessly at low speed but knocks when it's faster. Or a pitted bearing with the same behavior. Hard to say without opening the motor up.

It's not impossible that it could be a controller based phenomenon, but it's very unlikely.

 

[docw009]

I used to test my motors in an old 135mm fat bike fork that was clamped to my desk. Sometimes there would be some resonance or a rhythmic clicking if I didn't keep the nuts tight. when I spun them up.

There is also the possibility that you wired up the motor with what the experts here call a false positive where it appears to spin properly when slow, but goes out of sync at higher speed and doesn't have the torque to pull a bike, making noises and pulling high current. You have to switch the phase and Hall sensor wires.

https://electricbike.com/forum/filedata/fetch?id=143752&d=1635586612&type=medium