BBS02B 750W overheated - problem

Hello,
I am looking for expert advice what part of engine may have been damaged. The problem occurred after 15 minutes of driving with full power in the muddy terrain. The driver showed the check engine icon and the engine stopped and it was very hot. After cooling, the engine works very loud (like a tram) and after a while it turns off. I opened the engine but I can not determine what is damaged.
I hope that someone can find out what is damaged.
1. engine rotor and its gear looks fine, bearing works fine for me
2. pinion gear looks fine and its bearing works fine - but its end looks like overheated.
3. nylon gear looks fine and its bearing works fine
4. biggest gear looks fine
5. engine core smells like overheated

I put photos and video on the dropbox:
https://www.dropbox.com/sh/z196of815rkjsb6/AAAfOms5nvBisHJ66XCiLEJfa?dl=0

windings are discolored. They might be toast

I had same symtopms. After cooling down motor worked but can only run on 200W. Anything more will overheat it. My windings are black burned. I have BBSHD now, it is much better motor for running at 800-1200w .

Anyone can advice, where can I buy engine core replacement (stator or stator+rotor) in Europe or in China? Unfortunately Bafang doesn't replies.

Kova_PL said:

Anyone can advice, where can I buy engine core replacement (stator or stator+rotor) in Europe or in China? Unfortunately Bafang doesn't replies.

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try declic-eco in France, as a custom order. The owner is specialized in BBS repairs.

Kova_PL said:

Anyone can advice, where can I buy engine core replacement (stator or stator+rotor) in Europe or in China? Unfortunately Bafang doesn't replies.

Click to expand...

Green ebikes kit - google search it

Even greenEbikeKit don't have it. They will try to rise quanity to get it from bafang. It looks like the USA is the only source.
I decide to rewind the engine.

The Hall sensors are easily damaged by overheating. They control the timing of the current to the motor, so if damaged the motor won't run smoothly and could get hot fast. The halls usually fail before the motor insulation.

The windings changing color is the insulation being overheated from too much current. If it gets too overheated it may fail and short. Rewinding might be required. This is a sign of running in the wrong gear. Downshifting to run the motor faster will reduce heating. Torque comes from current, but heat comes from current squared so run in the gear that allows the motor to spin near max RPM for lowest heating.

Bafang parts have been a problem. When buying a kit, choose a dealer that carries spare parts, but most do not and the factory does not seem to either.

Thank for advice with Hall sensor. I have run motor without nylon gear. Works the same - heats 80°C in 1 minute, its laud, works not fluent on one throtle setings (A changes) and it stops from time to time.
Windings are black so it have to be changed. If it don't help I will have to replace hall sensors fallowing your advice.