Hi, my knowledge of motors tells me that poles of motors affect torque for a given amount of energy input. Imagine a motor with only 3 poles. Each pole provides 1/3 the energy required to turn the rotor. The torque will be high initially but must turn 120 degrees before receiving the next amount of energy. The point of rotation between the poles will be weaker and the motor is not as responsive to changing demands....

Now imagine a motor with 6 poles. The poles shares the same energy over a different point in the 360 degrees. 1/6 energy in twice the number of locations. The initial torque is less at the pole but it gets a second push of energy as it passes the 2nd pole pair. The area between poles is less and will be more responsive to changes in power inputs.

So the torque is less with more poles but has a smoother response to changing input...

aylwardm there is a "breakeven" number of poles regarding efficiency...otherwise infinite poles would be the answer :-)