Still searching for a motor to put on a conversion that uses a torque sensor. I see bafang has the ultra series but it is not for conversion. Only for custom designed frames to mount it.
I have about 5,000 miles on my 750w Tongsheng TSDZ2 with open-source firmware/blue nylon drive gear and it has been doing the job for me.
My use case:
- ICE Adventure HD tadpole trike
- Rohloff 14-speed geared hub
- 200-pound, 82-year-old rider
- Moderately-hilly terrain in SE Penna about 23 miles west pf Philadelphia
- 90% paved sidewalks and multi-use paths, 10% dirt and grass.
- 700 wh 50v battery kept between 20 and 85% of max charge.
- Use of pedal assist mostly restricted to too-steep hills , particularly heinous headwinds, and situations where I want to accellerate quickly and hold more speed (as in the occasional calculated risk situation where I wind up riding a few hundred yards on an automobile road)
I find the noise level acceptable with the nylon gear - and I have been accused of being neurotic about noise. I suspect I would find a brass or bronze gear tb too loud.
I have the motor capped at 350 watts and it seldom breaks 250 even on the steepest hills at 3 mph in lowest gear.
The only gotcha I have found is that when the 860c display bit the big one, the replacement display had a different version of the firmware on it and I had to buy a little interface thingie and figure out how to re-flash the new display with the same firmware version as the motor.
Other than that, the TSDZ2 with open-source firmware has been the cat's ass for my application and I would not hesitate to do it again.