Yes, the motor will spin faster in direct proportion to the voltage, but it also needs the power to reach the higher speeds. If you don't give enough power for its higher speed, it'll run inefficiently and get hot, but if you give it too much power, it'll also run hot anyway. It'll probably be OK for around 1000w from the battery - say 18A at 52v. It all depends on your rides. It won't be any good for off-road stuff or steep climbs at much more that 48v.
I have been experimenting.I rode 3 miles using 600/700 watts@48 volt and the motor was not even warm.Dapu said it has 45Nm of torque.Hills really stressed it @36 volt
Controller has 100v caps.I pedal this bike alot&DD hubs really slow me down.Right now I have a 13s 3p battery on the bike but I have some cells&was thinking of adding in series 3s 3p.I really like this little motor
No motor has torque because it's a variable that depends on external parameters, like volts, amps and speed. It's more or less directly proportional to current and voltage. Stepping up from 36v to 48v gives an instant 30% increase in torque. If they quote a torque figure, they have to qualify it by mentioning the speed, volts and amps.
