MOTOR:
The motor has three phases, or power supply wires (think of this as a 3-cyclinder automobile engine.) Each of these phases fires in succession with the others, determined by the "Central Brain", or what is called the "PWM (pulse width modulation) Controller." Inside the motor on the outer perimeter there are many "rare earth magnets". Closer to the center of the motor are the wire coils, also wired in three phases. As a pulse of electricity is sent to the motor from the controller the coils create a strong magnetic field, which repulses them from the magnets and causes the motor to advance (rotate) away from the magnets. The controller then sends another pulse of electricity and the next phase fires, rotating the motor even further. It's helpful to think of our automobile engine example: 3 cyclinders - each firing one after the other.
There are three power (phase) wires going into the hub motor, and five Hall Effects Sensor wires coming out of the hub motor. The Hall Effects wires are used only to help the motor start from a dead stop. If you have a "Pedal First" controller (this controller requires that the bike be moving 3-5 mph before the motor will kick in), the Hall Effects Sensor wires are not needed.
WORD OF CAUTION: the Hall Effect Sensor wires are thin, delicate wires that can be broken. The most common reason these wires get broken is because the nuts, which secure the hub motor/wheel on the front forks are not sufficiently tightened. If the nuts are loose, there is a possibility that the motor will spin within the forks, wrapping the cable into a ball, and severing the tiny Hall Effects Sensor wires. In many cases, you cannot visually see that the Hall Effects Sensor wires are broken. When the Hall Effects Wires are severed, the motor will not fire properly, i.e., the motor will vibrate or "chatter", in much the same way that an automobile engine will run badly when one of it's cyclinders is not firing. Many people mistake the "chattering" for a bad wheel-center bearing, when it is really severed Hall Effects Sensor wires.

CONTROLLER:
How does the controller determine the speed at which the motor rotates?
The pulses of electricity sent to the hub motor are determined by the throttle, which is mounted on the handlebars of your bicycle. The throttle is actually just a magnet passing by a "Hall Effects Sensor." Power is supplied to the throttle from the battery. The throttle then rations a small amount of power: from 0 to 5 Volts, which it sends to the controller. The amount of voltage sent to the controller is determined by how much the throttle is twisted. As the throttle is twisted, "Hall Effects Sensors" read the amount of voltage, and send this amount of voltage to the controller. 5 volts means the controller does nothing: sends no pulses to the hub motor, 0 volts means the controller sends electrical pulses to the hub motor as fast as it can.

BATTERIES:
This Electric Powered Bike Conversion Kit is a 36 Volt system. In your battery pack (which mounts on the rear rack of your bike), there are 3 - 12 Volt batteries connected in series, which adds up to 36 Volts. These are sealed, gel-cell, lead acid batteries. Lead Acid Batteries need to be recharged immediately after EVERY use. They hate to be left in a discharged state, even if they are only slightly discharged. I repeat, THEY HATE TO BE LEFT IN A DISCHARGED STATE! So, if you forget to recharge your batteries, leaving them drained for even one day, you WILL damage them, and they will soon begin to give you poor performance.
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