I acquired a few NOS MP2s earlier this year, and I've yet to run one of them myself.  I installed one for a gentleman whose e-bike was stolen.  He ran it at 36V and was raving about the regen braking.  I just picked up a chopper (Nirve Cannibal) and I want to run one of the MP2s in front.  I'll first weld a disc tab on the fork.
Anyway, I'm wondering if I can safely run this motor with a 52V battery.  If fully charged, it would be at 58v.  Is that too high for the stock controller on an MP2?  I like the "cleanliness" and simplicity of the internal controller, so I'm hoping that I can keep it.  Would it play nice with 52V?  I just bought the 52 for my other bikes, and I'd live to use the same battery for all of them.  Thank you for any thoughts and/or input you're able to offer.