I actually did this, also found the same problem as the 750 motor isn't compatible.
So I purchased from Eunorau 48v 1000W Bafang motor with the cable on the rotor side. (the same motor linked earlier in the thread RM G062.1000.D)
I was about to begin my install and realized the "1000W" is smaller then the 750W motor I just attempted to install. Any insight on this? its similar to the stock rad motor In size and perhaps just peaks at 1000w?
Anyway I went down a rabbit hole and ended up trying to install the 750W motor with the 1000W motor housing, had to nip and tuck some wires. Ultimately, the 750 W motor spun backwards. Which I anticipated, however after reading some forums I was under the impression I could swap any two of the larger wires inside the connector and it would reverse the direction. That didn't work.
So basically we scrapped the whole project, luckily I never touched my stock motor. So who cares right?
IM back to square one and im thinking of purchasing the 1000W motor AGAIN and trying just to swap the internals. As I mentioned they are small enough, it should fit into the existing housing. But im going to take a break from failed projects for a couple days do some reading and most likely attempt to install the 1000W motor I already have. (except I cut off the connector to use on the 750w motor, that will have to be addressed)
Long story short, why is the 1000W smaller then the 750W? Does that matter?
If there's a possibity I was wrong and the 1000W Bafang motor is indeed a true 1000W ill gladly fix it and try again or purchase a new one.
It just seems unlikely as the technology looks the same, and its significantly smaller then the 750.
excuse me for being long winded.