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Old 11-28-2018, 06:05 PM   #20 (permalink)
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Originally Posted by jray3 View Post
Now back to motors for conversions. Analogous to rotor tip speed with helicopters, the speed of the commutator under the brushes is a limiting factor on series wound brushed motors, which is proportional to the motor diameter. So a larger motor will have more starting torque, but a lower top RPM.
Actually, the rpm limit on my kostov is due to the windings not being restricted. Similar to most +13 inch series motors. The comm flies apart next.

The fix is kevlar banding, but at only a 1000 or so more rpm. Back EMF @ 6000 rpm kinda sucks big time, too
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