Post Mortem on an E-bike motor

 Sometime around mid-summer, my partner's e-bike motor failed.  Given that this was during prime biking season and therefore somewhat of a crisis, I just order a replacement and switched the insides, setting the old motor aside for inspection later.

This past week, I took a morning and investigated a bit further.

I started by removing the drive gear.  Only three little screws.  Then I hooked up the puller to remove the rotor.  This part was easy to get off but there are strong magnetic fields here and it's not possible to pull if off by hand.

Once off, it only took a few minutes inspecting to see what had happened.  For some reason (to be determined later) the rotor rubbed against some of the windings on the stator and shorted them out.  Wear marks were clearly visible and some of the wires had the insulation worn off.

Next steps are to figure out why the rotor rubbed against those coils AND what can be done to rehabilitate the motor.  The rotor sits on a bearing that is visible in the picture.  I don't know if there is anything that keeps that bearing in that position or not.  I'm also thinking that I might be able to paint something on the worn wires that would sort of restore them to original condition, but that's for another day.