What does the motor power mean and what do I need?
Types of Motors
Hub Motor: a hub motor has internal gears inside its casing and is located in the hub of the wheel (usually the rear). Having a geared system will help you travel freely when not using the motor (no resistance due to its internal parts) but also means that the motor will not help you to stop the e-bike when going downhill, so your brakes will work harder.
Mid drive motor: A mid-drive motor sometimes referred to as crank drive, is located between the pedals and diverts the power directly to the chain itself, followed by the whole system.
How the Motor Works
Inside the motor, you will find a couple of wires wound around a series of circular poles forming what is known as a stator. Inside or around the stator, you have circular permanent magnets which make the rotor. As the rider uses the motor controller to draw current from the battery into the wires, it turns the stator electromagnetic. The permanent magnets on the rotor are attracted and repelled by the electromagnets, spurring a spinning action.
Power Ratings
250w, 350w, 500w, 750w, etc... This is usually the first thing you see for the motor. This is the continuous power the motor can deliver but you may also see a second number, Peak, which means the motor may go up to this much power for a short time, when needed and then go back down to the continuous power. For example, you may see a 250w motor, with a peak of 500w. So if you are going up a hill, it may go up to the 500w to help out but only for a short time.
Torque
This is shown as NM and determines how hard and fast the back wheel can be turned. This is important for getting up to speed fast but most important when trying to get up hills. For standard use, 40nm to 60nm should be more than enough torque. If you are looking to do serious hills, you may want 60 to 100nm.
Comments