By 1898 a rear wheel drive electric bicycle, which used a driving belt along the outside edge of the wheel was patented by Mathew J. Steffens. Also, the 1899 Template:US Patent by John Schnepf depicted a rear wheel friction “roller-wheel” style drive electric bicycle. Schnepf's invention was later re-examined and expanded in 1969 by G.A. Wood Jr. with his Template:US Patent. Wood’s device used 4 fractional horsepower motors; each rated less than ½ horsepower and connected through a series of gears.
In 5 years of working as a bike messenger in Minneapolis, I've ridden all kinds of bikes, in all kinds of weather. I've ridden walmart mountain bikes, 80's classic steel road bikes, kitted out Treks, pretty much everything EXCEPT for fat tire bikes. Such wide tires always seemed... too much. No need for a bike that only makes itself worthwhile maybe two months out of the year, I thought.
With a chain drive transmission, a chainring attached to a crank drives the chain, which in turn rotates the rear wheel via the rear sprocket(s) (cassette or freewheel). There are four gearing options: two-speed hub gear integrated with chain ring, up to 3 chain rings, up to 11 sprockets, hub gear built into rear wheel (3-speed to 14-speed). The most common options are either a rear hub or multiple chain rings combined with multiple sprockets (other combinations of options are possible but less common).
The federal Consumer Product Safety Act defines a "low speed electric bicycle" as a two or three wheeled vehicle with fully operable pedals, a top speed when powered solely by the motor under 20 mph (32 km/h) and an electric motor that produces less than 750 W (1.01 hp). The Act authorizes the Consumer Product Safety Commission to protect people who ride low-speed electric vehicles by issuing necessary safety regulations. The rules for e-bikes on public roads, sidewalks, and pathways are under state jurisdiction, and vary.