Bafang G510/M620 Motor wont start after repacking grease


New member
Local time
12:52 AM
Oct 10, 2023
I am newer to ebike repairs. I have a G510/M620 Bafang motor, I regreased the motor gears and put back together and one wire pinched (tempature), I was able to start and ride it, after shutting off it wouldnt start again. I repaired the tempature wire but still doesnt start. I could use some advice on if you think it is just the controller or if I need to replace the display or what else could cause this.

Tested battery and power coming into the motor.
Get yourself an e-bike tester. I recently got one on Amazon for $12 - e-bike tester. It can test just about every system on an e-bike. I thought I might have had a motor problem on my bike, but it turned out to be a bad throttle.
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There are generally several indicators of power on the bike, lights on the throttle, battery, display, what do these show?

"it does not start" could mean no indicators of power whatsoever, or just that the motor does not move.

initial guess would be a controller shorted out from exposed copper on the pinched wire gounding out and popping the circuit in the controller, but that is a guesstimate based on minimal and incomplete information.