What sort of motor power is available for ebikes?
Motor output/battery capacity is capped in the USA at 750 watts. Any motors with power greater than this may be subject to tax and motor vehicle regulations. Think of wattage as the size of the gas tank. The measurement of a motor’s output is calculated through the combination of 2 factors: battery AMP hours multiplied by battery voltage. AMPs measure the capacity of the battery and Voltage measures the strength of the electrical source for a given level of current.
Put simply, the more wattage you run through the motor, the faster you’ll go, up to a point. This point is determined by the gearing (how many gears your ebike has, the size of sprockets and the size of the wheels) of the bike as this will ultimately determine what the top speed is.
Many ebikes are hub driven meaning that instead of integrating the drive train with the chain and sprockets, it is connected to electromagnets which create the force which rotates the hub forward. With a mid drive bike you can change the gearing by swapping out a sprocket, swapping in bigger sprockets will allow the bike to travel faster. Some higher speed bikes may not have the longest lifespan due to wear and tear on the bike components when placed under excessive strain.