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Old 09-28-2012, 08:27 PM   #23 (permalink)
mort
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Quote:
Originally Posted by madmike8 View Post
I think you need a transmission or steeper gears in the rear. Motors are more efficient at higher rpms. Driving at 40-50 your burning more amps since the rpm is around 2k. A transmission would allow you to keep the motor in a more optimal rpm for a given speed.
Actually:

Quote:
Originally Posted by thomason2wheels View Post
Ok, now i want to ask a serious question. If the driveline was goin through a 4 or 5 speed tranny, would allowing the motor to turn more rpms in a lower gear reduce the load on the batteries?
Yes, but only a little. Any transmission will waste some power. If your first gear is 95% efficient and you get up to the 91% efficient motor rpm then the over-all efficiency in first gear is 86% which is better than the 80 - 85% you'd expect without changing gears.

But imagine a 3:1 first gear, I'd like to have that 180 lb-ft (3 x 60) at 10 mph.
-mort
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