I am not sure if question should fit in small scooter, larger scooter, or bicycle - here is a pic of my ebike:
http://item.taobao.com/item.htm?id=9945325151
I just bought it a few days ago for about $100 and would like to make it my project bike. I hope to use it not so much for inner city cruising - I am putting an electric motor on my folding bike for that - but to ride out in the suburbs, and even further. This bike has a place for 2 motors - I am looking into options for putting a small gasoline or alcohol powered - even propane - generator in the second battery compartment that will give me a long range - the introductory steps to making a hybrid.
I have 2 questions: First, I would like to put a 500-700 watt geared hub motor on the front wheel. The motor I am looking at, at the low end, weighs about 7 pounds. It has a suspension on the fork. I know that when converting bicycles to ebikes, putting a hub motor up front on a suspension fork is something to consider carefully, but the parts all seem to be steel. I have read of people successfully doing this with a steel fork and suspension parts. I am going to put a chain drive system on the rear wheel. I want the hub up front as a back up, in case something goes wrong with the rear drive system. I also will consider some way to use both motors if I am negotiating a steep road.
The sla battery and hub motor on the bike now are quite heavy and weigh about 80 pounds. The 2 motors I am looking at, the drive trains, lithium x batteries and even the generator I am looking at have a combined weight of less than 85 pounds, so my changes will make the bike weigh less than its original weight.
Sorry...i should have said that it has a place for 2 batteries, not 2 motors...but that is not going to stop me from installing 2 motors :)
For a front hub motor, you will also need a controller. I can't tell from the pic, but maybe a 22" rim?
You could try a 9 continents or an Aotema. A torque arm usually is needed. I ride an Aotema
You are adding maybe 12 lbs. I don't know what you can get that weighs 7 lbs. Maybe something slower with gears.
The 9C and Aotema are gearless and over 500 watts and can handle 36, 48 volts and maybe more.
But if you have to pedal or ride without power, the motor magnets cause a drag. Regen is possible and you could theoretically use the front hub to slightly recharge the batts. With gearless there's no magnet drag, but probably no regen. I'm also not sure that a geared motor is strong enough.