Noise from motor Radwagon

[Barkme Wolf]

I have been getting an intermittent hum when the motor kicks in. More when it is up near 500w. Sometimes for only a moment and sometimes longer. Just started a couple days ago. I have made no changes or had any trouble. Seems to work fine but the noise is troubling. I am at 5700 plus miles and this is the first time I have heard it.
Sounds like something is rubbing a little when the motor kicks in.
In between the noise there is no trouble and the motor is performing the same as always.
Getting my spokes switched out soon, will have the motor checked than.

 

[J.R.]

It seems to me you are describing a harmonic vibration. I've had that happen on both ebikes, one direct drive hub and one geared hub. The solution for me was to tighten the machine screws on the side of the hub motors to between 4 and 5 newton meters with a torque wrench. To help keep them tight, a drop of blue loctite can be used. If just tightening, do in a star pattern as you would lug nuts on a car rim. If adding loctite, remove one at a time, add the loctite and torque and continue in a star pattern until all are tight.

 

[Barkme Wolf]

It seems to me you are describing a harmonic vibration. I've had that happen on both ebikes, one direct drive hub and one geared hub. The solution for me was to tighten the machine screws on the side of the hub motors to between 4 and 5 newton meters with a torque wrench. To help keep them tight, a drop of blue loctite can be used. If just tightening, do in a star pattern as you would lug nuts on a car rim. If adding loctite, remove one at a time, add the loctite and torque and continue in a star pattern until all are tight.

Thank you, I will mention it to my mechanic.