KT (Kunteng) controllers are a popular choice among electric bike builders. A large selection of different displays is available, from standard LED indicators to color LCD screens. Most displays allow easy access to many important parameters.
P1 – parameter determines the transmission ratio for motors with a reduction gear. This is important in order to calculate the correct speed as the motor and the wheel rotate at different speeds. The value is a ratio between 1-255.
P2 – determines the frequency of the hall sensor signal per revolution, important for determining the speed and position of the motor. The most common values are 1 and 6, 0 disables sensor reading.
P3 – determines the relationship between the throttle and the level of cranking assistance. At 0, the crank assist level determines how much the bike accelerates when the throttle is pressed. Setting to 1 makes the throttle switch work regardless of crank assist level.
P4 – by setting the value to 0, it is possible to start from the spot only by pressing the throttle. With a value of 1, the controller only allows the throttle to be used if the motor is already activated (by cranking or moving).
P5 – determines the way the current capacity of the battery is displayed (discharge curve).
C1 – crank assist setup, depending on the sensor and the magnets attached to the crank, it is necessary to find the right combination that is compatible with your sensor.
C2 – determines how the motor phases are wound, if the wheel vibrates and does not rotate normally after changing the controller, this value is usually set incorrectly. It is possible to choose a value between 0 and 7.
C3 – determines the level of cranking assistance selected by default when the bike is turned on. 1 is the weakest and 5 is the most powerful.
C4 – the function depends on what value you set for parameter P4
C5 – sets the maximum power output for the controller. For example, a 30 amp controller with a C5 value of 3 will only operate at 15 amps.
C6 – LCD backlight strenght 1 – 6
C7 – value 1 enables cruise control, 0 disables this option. To use the cruise control, drive with the throttle at a speed of about + 15km/h, keep the throttle active in one position and at the same time press and hold the up arrow. After a few seconds, the letter C or the yellow text Cruise will appear on the screen. The cruise control is automatically disengaged when you crank a few revolutions, momentarily press down on the throttle, or press down on the brake lever equipped with a brake switch.
C8 – value 1 turns on the engine temperature display.
C9 – password setting. 1 turns on the use of the password, after saving the value, the user is asked for the password number 0 – 999. NB!!! In case you forget the password, to unlock the device you have to use the same type of display that can be used to delete or replace the password, all other parameters will also be replaced.
C10 – restores the default settings, the controller may not work correctly with components after that.
C11 – defines the communication protocol used between the controller and display, modification of this parameter should be avoided.
C12 – determines the minimum allowable voltage. If the battery voltage falls below this value, even for a moment, the motor switches off.
C13 – motor braking and charging. A relatively risky parameter. With a value of 0, there is no motor braking. A value of 1 is the weakest and most effective way to regain energy. NB! On long descents, there have been several cases where various components (mainly the controller or the battery) have overheated and been damaged due to heavy loads.
Values 2-5 increase braking power but don’t increase regenerative charging efficiency. There is an increased risk of damaging the fork openings with the motor shaft, as there are large torsional forces at play. You can read more about motors in the article “How to choose a motor for an electric bike”
C14 – cranking assist power. 1 – weak, 2 – medium, 3 – strong