How fast can an electric bike legally go?

The maximum speed that an electric bike can legally go depends on the country, state, or province where you are riding. In the United States, for example, federal law defines an electric bike as a bicycle that has a motor with a maximum power output of 750 watts (1 horsepower) and is limited to a top speed of 20 mph on level ground when powered solely by the motor. However, some states and localities may have different laws and regulations regarding the use of electric bikes, so it's important to check your LOCAL laws before riding.