what ev folk really need is a 1.5 to 2.00 horsepower rear bicycle hub that will give enough power to go-plus a good lithium ion battery pack with proper charging and discharging electronic control at a reasonable price. most powered hubs now seem to be under powered as far as output power. A bike is a bike-but its rugged enough to be propelled 20 0r 25 mph . Some bicycles out now have large diameter spokes -very robust . Ideally the hub should be supplied as a whole wheel with heavy duty spokes ;26 inch; and free wheeling built in.One argument -upgrade to a motorcycle-No!! nothing like a bicycle! A powered one! A powerful hp hub will draw a lot of power-however once moving the bike will coast a long way