Loose front bearing slot on Neu motor

[othello]

>It's honestly baffling to me as to what may have caused this

I had the same issue with my Neu 1515. Reason beeing a crappy motor mount. If you can push the rear of your motor somewhat to the side with your fingers while beeing mounted than chances are good that due to shocks while driving the motor shaft changes alignment to the spur and the pinion is pressed against the spur which over time results in a gap where the front bearing sits.

Did you have to change the spur and/or pinion oftenly due to wear? Did your pinion often came loose? Those are signs that the motor is able to flex when mounted.

A stronger motor mount remedies those issues. Maybe you are able to support the rear of your motor too.

I changed the front bearing, wrapped the new one with alu foil and glued it back into the can. Doesn't sound like a new one and i can feel some slight vibrations (rotor has some scratches from dust and is not perfectly balanced any more) but it still does its job.