I seem to have damaged a stator on a hub motor, working but makes unpleasant noise

Video here:

In summary, a wave spring washer inside the hub split itself open and got itself busted to pieces.

The rotor/wheel seems to be fine and operates normally on either stator.

Stator doesn’t seem to have any damage I can detect. it does’t look to be harmed in any way at all, but makes noise with either wheel/rotor.

Any thoughts on what may be happening, or ideas for me to try?

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my assumption is that the washer is just for th bearing to operate. just like speed washer on normal wheels. as the motor will be bolted on back of stator i dont think it is a huge problem. beside that spring is so small and thin. it doesnt help. I would put some normal washer to fit in. bad stator may have been bent or moved some how so maybe u can check the bolts on truck that keeps the motor in place? the large 4 pass the stators i mean.

The spring washer is a cheap way of not needing tight tolerances in the machining.

I wouldn’t trust something like that to hold the motor can out. The reason you want no play is it will eventually wear the bearing shaft and your get rattling, especially at speeds. I expect it will still work without it, but probably not as long as with it. I wouldn’t trust it to last long either way though with that design.

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How’s the bearing shaft going to wear?

If you the bearing can slide on the shaft, you have metal rubbing on metal. If you put it together and it can slide side to side, that is, which seems to be the case if you don’t have that washer in there.

Another solution is to put the correct sized washer so theres no play at all. The spring washer seems like they were asking for trouble.

It might take 100’s of miles to start showing, but it will. This was a problem we encountered in developing hummies hubs. We solved it by simply having super high tolerances here, and also, using retaining fluid to fill in any slight imperfections.

You sure it was a problem with the bearing sliding side to side and not spinning on the shaft?

I’ve noticed this happens when people don’t run bearing spacers on normal wheels, instead of the inner race being stationary with the shaft it spins because there’s nothing holding it in place.

I can totally see that becoming a wear factor with enough miles, but side to side motion. I’m having a hard time imagining that happening enough to accumulate damage.

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Maybe at some point, it becomes that. But at first, it starts to wear from the side to side movement. We fixed the problem by tightening the tolerances so the c-clip fits perfectly to remove side to side play and the issue went away, even without retaining fluid. Hummie has been riding the latest motors without retaining fluid and we didn’t see any wear.

Checked the stator for any movement or misalignment. It looks fine that way.

But I did notice I did have definitely have a short in the coils. Two neighboring windings got pretty effectively smeared into a single conductor.

Could the noise be electrical? I would effectively have an imbalanced number of turns now.

oh no thats busted. but it will work fine u will loose some torq on one side. clicking noise can be electrical for sure. unless the wire is cut, try re insulate with epoxy or super glue.

@CHAINMAILLEKID this hub motor is 30$ on their website so just replace it and you’re good. They are using your videos on their website so you’ll get it free probably or maybe you can test their H9 and check those new hub motors with thicker thane . I would love to see your review :wink:

Yeah, I have their direct email and stuff. Getting it replaced shouldn’t be a problem.

But this is more to satisfy my curiosity and learn stuff.


That’s why I love your videos :wink:

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