A common cause is to skirt importation laws. This is where things get complicated though, because ebike manufacturers don’t always rate their parts this way. An ebike with a 48V battery and a 20 amp peak controller would theoretically be capable of a nominal 960 watts of instantaneous power. The maximum current is determined by the ebike’s controller, and is usually somewhere between 15-30 amps. You just multiply the voltage of the battery by the maximum current the ebike can handle. So an ebike motor connected to a 24V battery being supplied with 10 amps of current would be powered at 24*10=240 watts.Īs you can see, calculating the peak power of an ebike is simple. The number of watts used by an electric motor at any moment equal the voltage supplied by a battery multiplied by the current flowing from the battery to the motor. Watts can be used to measure the instantaneous power output (or input) of a machine, such as the electric motor on your ebike. A “watt” is a unit of power, named for Scottish Engineer James Watt. Let’s start with some definitions and a bit of a physics lesson. The problem is that manufacturers don’t use the same standards to name their motors, and consumers often don’t understand the differences. Nearly every retail electric bicycle and ebike conversion kit is listed at a specific power level, such as a “500 watt electric mountain bike” or a “250 watt ebike conversion kit”, yet often this power rating is misleading or just plain wrong.
