While we are talking about "perfect world" scenarios for motors...
Motor rpm is determined by internal pole count.
My brushed motor has only four magnets and therefore two pole pairs.
Most RC motors have 14 magnets and seven pole pairs.
As you increase pole pairs it reduces the motor rpm because it takes more electrical cycles to get one physical cycle out of the motor.
One could imagine a motor with 40 magnets and 20 pole pairs that was done as an axial motor with Halbach Arrays and carbon fiber. (like above) If you placed such a motor on the bike as a "chainring replacement" then you could eliminate all the "motor-to-bike" adaptation issues.
The problem has always been that we are using generic or other purposed motors and never designed for the unique needs of an ebike.
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Last edited by safe; 02-20-13 at 11:07 AM.