Yes, the 36V "328" seems like the best choice to me as well. I'll be doing something along those lines when I get home in a few weeks[need to order stuff now
Using the Ebike ca to play around, and the Ezee 20" @ 96% throttle as a substitute, I get-
Single motor[17.5 A controller, 46V batt.],
10%-10.5 mph, overheat in 15 min.
15%-5.5 mph, overheat in 5 min.
No-load speed-25 mph
Frt. motor[17.5 A controller, 46V batt.],
Rear motor[23A controller, 46V batt.]
10%-20.5 mph, overheat-never
15%-17.6 mph, overheat-never
No-load speed, 27.6 mph
I would be inclined to run 10S[39V] instead of the 12S for,
10%-19.5 mph, overheat-never
no-load speed-24 mph
A more reasonable speed to pedal with possible ratios of 11/44, 11/48 or 13/48 and little loss in climbing ability.
With this set up, I think simply running both motors all the time might work well, as I see little loss in efficiency[never really a big concern to me]amd it spread the wear and tear over two motors.
I assume with a higher voltage, a switchable motor control would be preferable.
At any rate, those things would easy enough to play around with during testing.