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Old 11-06-2012, 04:59 PM   #9 (permalink)
Extreme DIYer
Join Date: May 2012
Location: Bowling Green, KY
Posts: 29

Custom eBike - '89 Bianchi Mainstreet 24vdc motor w/ 24v/30ah LiFePO4 Battery Pack

2006 Prius - '06 Toyota Prius 2
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The short answer is, you can't. If you want speed, you will need higher gears. If you want to climb hills, you will need low gears. If you've ever ridden a one speed bicycle, that will give you a basic idea of the need for more gears.

165W motor could do a lot if you are at speed (above 12mph) on a level surface but (some velos only need 80W's to maintain 12mph (level surface)), climb even a slight upgrade or take off from a dead start and 165W is virtually useless (even for assist). This is especially true for a 500+ lb vehicle. With a vehicle that size/weight, I would recommend at least 2.5hp or 2000W (for assist with gearing).

As for programming AC motors, this is done by motor controllers. The more poles the motor has, the more it can be controlled but even then it is only done by halving the AC frequency. For instance, a 2 pole motor with a 115vac 60hz input will have an rpm of about 3600 (minus losses), a 4 pole could have 2 speeds (1800 or 3600) an 8 pole could have 3 speeds (900, 1800 or 3600). This limitation would necessitate gearing. This is why DC motors are typically used for transpo.
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