deronmoped
10 kW
- Joined
- Oct 6, 2008
- Messages
- 706
Well, I burned up the motor in my Giant LaFree.
I have several LaFree's, the 2002 year model. The motor mounts to and drives through a transmission and then the rear seven speed cassette. I have two stock 24 volt bikes, two modified bikes one runs at 36 volts, the other I was running at 58 volts. Well the 58 volt version burned up the motor after only a few dozen miles. Seems the commutator gets too hot and the segments come loose. So now I'm looking for a replacement motor. I tried a Ford Taurus radiator fan motor (12 volts @ 45 amps stock) at the 58 volts and that encountered the same commutator problem. So now I started looking at the RC motors. One, to get away from brushes and two for the light weight power. I would go for a regular brushed higher power/voltage motor, but as long as I moding things, why not try something that might be even better. One thing I'm thinking is, if this works, I would have a solution for any of my other LaFree's when the motors go south.
I checked where the motor inputs to the transmission and the ratio is, for every time the rear wheel turns (in low on the cassette) the motor turns thirty times. I know the RC motors are geared down to drive the rear wheel, but I don't know the formula. I don't care to build a transmission, so if there is not a RC motor that would work with that ratio, I will be looking for a different motor solution. At 30 to 1, is there any RC motors that would work?
I have several LaFree's, the 2002 year model. The motor mounts to and drives through a transmission and then the rear seven speed cassette. I have two stock 24 volt bikes, two modified bikes one runs at 36 volts, the other I was running at 58 volts. Well the 58 volt version burned up the motor after only a few dozen miles. Seems the commutator gets too hot and the segments come loose. So now I'm looking for a replacement motor. I tried a Ford Taurus radiator fan motor (12 volts @ 45 amps stock) at the 58 volts and that encountered the same commutator problem. So now I started looking at the RC motors. One, to get away from brushes and two for the light weight power. I would go for a regular brushed higher power/voltage motor, but as long as I moding things, why not try something that might be even better. One thing I'm thinking is, if this works, I would have a solution for any of my other LaFree's when the motors go south.
I checked where the motor inputs to the transmission and the ratio is, for every time the rear wheel turns (in low on the cassette) the motor turns thirty times. I know the RC motors are geared down to drive the rear wheel, but I don't know the formula. I don't care to build a transmission, so if there is not a RC motor that would work with that ratio, I will be looking for a different motor solution. At 30 to 1, is there any RC motors that would work?
