Thanks for the replies.
Dan, I'm glad you mentioned the coasting limitation of a DD motor, I'd forgotten about that.
Regarding the number of turns, could you please check my calc for the RPM per volt of the Code 10 Bafang is correct?
Code 10 = 300 rpm (link
) @ 36 volts
............. = 8.3 rpm per volt ?
Which roughly ends up as a 7 turn for a 25 mph cruise (48v, 700C wheel).
As suggested, I'll start with greasing the Bafang gear ring to reduce the whine. That would be much easier than swapping motors... Fingers crossed!