Electric Bikes - Motor Question
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I have a 450w gear reduction scooter motor I'm about to install on my home built trike. The controller has leads for reverse, but in order to have a reverse gear, I'd have to install a fixed cog on the axle instead of a freewheel. Other than drag, are there any other drawbacks? One thing that concerns me is that it's a brushed motor, so maybe the brushes will wear out faster while I'm not using the motor. The motor is mostly for hills. Being diabled, I need some extra power up some of the hills around here. Reverse would be a nice feature, but if there are too many drawbacks, or potential damage to the motor, I'll just go with the freewheel and use "Flintstone" reverse.
gmouchawar
05-06-09, 12:12 AM
The drag will be too much. Go with the freewheel.
similor
05-06-09, 02:13 AM
As a brush motor, "Reverse" is very simply, just change the power polarity with a relay.For common use,motor(+) connect to battery(+) and motor(-) connect to battery(-).For reverse use,motor(-) connect to battery(+) and motor(+) connect to battery(-).Try it.
As a brush motor, "Reverse" is very simply, just change the power polarity with a relay.For common use,motor(+) connect to battery(+) and motor(-) connect to battery(-).For reverse use,motor(-) connect to battery(+) and motor(+) connect to battery(-).Try it.
Getting reverse isn't the problem. I could either use one of my controllers that has reverse leads, or use the Bosch type relays that I also have. I did try the fixed gear, and there is some drag, but once I'm at a decent speed, it's not a problem. I just don't want to damage the motor, and I'm not sure if spinning it "dry" has any ill effects. If it does, then I'll just go with the freewheel. I haven't hooked up any of the electrical parts, I just mounted the motor so far.
I guess the welding fumes are getting to me. DUH. This is simple. I ordered a second sprocket to add to the motor. So one chain will go to a freewheel going forward, and the other to a second freewheel going in reverse.