5055 Motor Pulled Itself Apart

I was taking my DIY board on its first test run. It is a 5055 10s sensored motor running FOC on the VESC.

I was going up a steep hill (I believe about 10-15% gradient) and heard a strange clicking followed by a strange whirring sound coming from the motor. After dismounting immediately I found that the motor seemed to have pulled itself apart and the shaft was out of place (see attached).

Anyone have experience with repairing motors?

Thanks, Max.

I have attached the photo of the original state of the motor

Below are videos of the motor in its broken state:

Video 1 Video 2 Video 3

Is the circlip still attached at the front? And is there a grub screw that holds the shaft at the can end?


Like @scepterr said it looks like the grub screw has stripped on the shaft and it has slid outwards. If you can’t get the shaft out you could try using grub screws again or use red loctite and never worry again

You just need to disassemble the can and axle and mount it again with Loctite where the axle and can touch. This issue is present on all motors

I’ve had this same issue with a 5065 motor from TB. Does anyone know the cause?

I think the set screw on the rotor(nipple) wasn’t tight enough on the axle and so was the glue that held it together. Maybe try and push it back and reapply loctite like @pat.speed said. Next time use a 63mm for hill climbing.

Dont know why but many motors come with shaft grub screw not screwed in at all :smiley:

It just happens sometimes because the force of moving a human is very large and if the shaft is only held by one grub screw it can sometimes strip