I didn’t already have a picture of the ID of the bearing got delayed going back and opening it up to get a better look. with a good 8mm shaft in it, there’s no play. so it seems like all the wear/corrosion was on the shaft side of things.
but still a todo to open it back up and double check.
Thats looks like glue inside the bearings, that worked as a sand paper, therefore broke the protection against corrosion…After oxidation started, you can not stop it. Maybe some loctite got into the bearings spacer when locking the motor pulley with the shaft…
Oh, that’s an interesting idea.
these motor pulleys did receive loctite 680 on the shaft, after tons of trouble keeping things tight with only loctite on the grub screws.
I always use loctite to glue the motor gear to the shaft, and I always leave the motor curing in a vertical position with the gear down for at least 24hrs (sometimes for 3 days)…Just to avoid that situation…
And now a 3rd motor with a similar problem. This is in a new to me used board I just bought. turns out it has a bit of motor growl and it looks to be the same kinda problem.
The growl:
The click, the play.
some dirty crap around the bearing this time:
inside bearing surface. ( lighting made the colors weird, black gook looks like ash)
magnets don’t look as bashed up as the original motors so this one hasn’t gotten as bad yet. was just noisy.
At least the cruft cleaned up easy 
cruft
/krəft/
noun
“this removes all unnecessary cruft from Word documents saved as HTML”
s/cruft/crap/ ?
Just put some bearing gap filling loctite. And go riding. Assuming bearing is fine
which loctite is that? 680 I’m guessing.
used to join fitted cylindrical parts. … Capable of filling diametral gaps up to 0.015 in. (0.38 mm)
Was considering this as a fix. been thinking how to get it in there just in the right spots without getting it everywhere. also wondering how you keep it from being “off axis” when it cures.
Also how you ever get it apart if you had to again…
Assemble as normal, put some of the loctite on the end of a pin, and just touch the pin to the edge of the shaft/bearing. Do this at a few points all around. It will wick into place.
If you do as above and you didn’t put excessive amount, 50% chance you can knock it lose again when you need to.
This seems to be a common issue with lacroix 6389 motors “maytech 6396 if you wanna count in the 10mm nipple”
One of them started doing it at only 50 miles got replaced under warranty but the new didn’t last much longer
I think it probably has something to do with either bearing or shaft tolerances or even shaft heat treat or whatever
One of my maytech 6374 just started doing it too but this one is around 1,300 miles new
I’d Ask maytech to replace the shaft/bearing or the whole thing. See what they say.
Lacroix said they weren’t Maytechs. ( at least for the prototipo motors. the first two I had fail. ) but said they’d reach out to the distributor about replacement shafts.
Well. They look awfully a lot like maytechs imo but who knows 
that they do.
responded that they couldn’t get them.
I’ve got this issue on both of my TB6374 motors - I had to re-tap the hole to larger M4 and then file the thread off the last couple milimeters of bolt so that when I screw and unscrew them into the shaft, they dont f*ck up the thread.
Agree with @Swish, actually that is the best solution if he wants to keep using them…Would fill the gap with loctite 638 (I have the 680, I do not like the way it`s work for this kind of things). So this is what I would probably do…move the shaft a few milimetrs, mount the bell again and use loctite 638, let it cure for 3 days (the motor standing up, let it dry just leave it and do not touch it at all, just avoid letting locktite into the bearing)…forget about replaccing the bearing, because if it´s fucked, it does not matter, apply heat with a tourch and your are good…
