Electric-assisted bicycles are treated as human-powered bicycles, while bicycles capable of propulsion by electric power alone face additional registration and regulatory requirements as mopeds. Requirements include electric power generation by a motor that cannot be easily modified, along with a power assist mechanism that operates safely and smoothly. In December 2008, The assist ratio was updated as follow:
Before you start shopping around for a new e-bike, the first thing you should ask yourself is, “how do I plan on using an electric bicycle?” How far do you plan on traveling? What type of terrain will you be traveling on? How much assistance do you need? Do you plan on pedaling – or do you want the bike to do all the work? Is this bike for daily commuting or casual riding? How fast do you need to go?
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.