There are two basic categories of electric bike, and their uses don't offer equal crossover value. The first category is essentially a normal bicycle that has been outfitted with an electric motor. These bikes are the same size as a standard bicycle, and handle almost identically, save for the obvious benefit of added motive power thanks to a motor and battery.
Photo: Zap Electric's power-assist kit turns a conventional bike into an electric one. There's a bolt-on DC electric motor (weighing just over 3kg or 7lb) just above the back wheel, behind the police officer's foot, pressing against the tire and driving it by simple friction. The motor's powered by a compact lead-acid battery (weighing about 5.5 kg or 12 lb) inside a protective nylon bag. This kit adds quite bit of weight to the bike, but gives extra range and speed when needed. Photo taken in Santa Rosa, California by Rick Tang courtesy of US DOE/NREL.
This Class 3 (28 mph), utilitarian, road e-bike is smooth and torquey thanks to its Bosch Performance Speed motor. With a drop bar and traditional road-bike position and handling, the CrossRip+ is more suited to longer rides on mixed terrain than navigating congested city streets. It comes with a rear rack—for mounting bags, not for attaching cargo directly—full fenders, a kickstand, and integrated front and rear lights (which are powered by a Bosch 500Wh battery). It features a SRAM Force 1x11 drivetrain, hydraulic disc brakes, and wide 700x38mm tires.
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.