Reinforcement of the rear wheel electric bike

[Abe]

Hello Alan,

From time to time the rear wheel on which the the motors is installed just released independently and falls.
All the measures I am trying to avoid it did not really help prevent dangerous phenomenon.
Do you have mechanical experience?
Abe

[Bikemad]

Hi Abe, do you mean the axle is falling out of the dropouts? 

If the axle is fitting into the dropouts correctly and the nuts are properly tightened it should not fall out.

If the dropouts are worn and the axle is a loose fit in the dropout it can sometimes work loose with constant acceleration and regen braking trying to twist the axle in different directions.

A torque arm can be used to prevent the twisting forces from turning the axle but if the axle is tightened correctly, it should not twist in the first place.

Sometimes it is necessary to file the slot deeper into the frame to allow the axle to fit in more, but you need to be careful that you don't file away too much metal and weaken the dropouts too much in the process.

Can you post a picture showing a close up of the axle in the dropouts so we can see if there is an obvious problem?

Alan
 

[Abe]

Hi Alan,
I decided not to take a risk with the motor cables are stretched so I purchased a torque arm arm as you suggest..
Thank you,
Abe