I am connecting a 400 watt electric motor to my bike, along with a inverter since the motor runs of ac power. I am trying to find someway of adding a new and separate gear onto my bike without damaging the bike, or welding anything, and making the device possibly removable. I am hoping to run a chain from the motor to the gear I added on.
The present in an electrical motor can expand at low angular speeds, the motor would overheat if it is furnished with rated voltage but most effective turning slowly. The bearings can also be broken via high axle loads too.
off the sprocket is about the only place - still requires spacing and welding two sprockets together imho forget it...
anything is possible if ya study it long enough. try different parts off of different things till ya find a combo that works. main thing is dont rush into it,patience and some good ol thinking on the problem can make anything work. look at all the custom rods out there with home made parts on them. think it out and you will make it work
The only way that i would attempt this would be using the existing gearing and using a 'jack-shaft' to drive the whole thing.The only problem with your idea is that inverters are not very efficient so the extra weight of the battery and inverter would cancel out any benefits.Think about a D/C powered motor and a wheel mounted generator to charge the battery.
Note that most electric motors can't be run at low speeds for long periods, or they'll overheat and wear out! Therefore the rated operating speed of your motor needs to equal the average rotation speed of your wheels at cruising speed, multiplied by the gear ratio. You will need to do some calculations. Your cruising speed should be around 15-20 miles per hour. That's around 20-30 feet per second. That's 240-360 inches per second.
