I have a similar LCD + Controller setup on 2 of my e-bikes.
Here's my suggestion(s):
- Within 5 seconds of switching on the LCD via the middle button, hold the top and bottom buttons down until you get into controller settings.
- You should see a flashing number. This is the motor speed limitation of the LCD. Use the top and bottom buttons to increase or decrease it. The maximum speed is recommended for the purpose of testing.
- Press the middle button once to move onto the next setting. Now you will see the wheel size at the bottom of the LCD flashing. Once again, use the top and bottom buttons to set it correctly.
- Press the middle button again and you will be able to choose your units of speed i.e. KPH or MPH, select the right one for you using the top and bottom buttons.
-Hold the middle button (power) to save settings and exit (LCD should NOT power off though). See how you go.
Now I've experimented with these eBay-Chinese LCD + Controller combinations a fair bit. My findings are as follows:
1. The speed limitation on the LCD cannot be overridden. It WILL cut the throttle/motor if you exceed this limit and will only provide power to the motor when the detected speed falls below the set limit.
2. If you try and cheat the speed limit by selecting a smaller wheel size in the settings menu (or changing between KPH and MPH), the motor will still reach the same maximum RPM, so this achieves nothing.
3. I tried swapping the LCD limited to 40Kph to one that was factory limited to 60Kph (swapped the LCD's between 2 e-bikes), yet the motor still reached only 40KPH unloaded.
4. This suggests that the controller itself may have some sort of RPM limiter.
5. The LCD uses the motor hall signals to determine what speed/RPM the motor is doing.
6. I tried doing away with the LCD (and its speed limitation) by leaving it unplugged and creating my own on/off switch on the controller, and using a Cycle Analyst I manually wired to the controller. The throttle would surge on full, then die off completely, then surge again etc quite erratically. The bike was unusable as an e-vehicle. Reconnecting the LCD fixed the problem. Now I use both the LCD and Cycle Analyst.
After thinking about my point above, the controller may rely on the LCD for everything, including feedback for the hall sensors for speed detection/limiting.
There are even more advanced settings hidden in the LCD. I'll copy and paste from a user manual I found online but Chinese-English is not so great. I hope you understand it better than I do.
After going into the main settings menu, press the power button three times, and all settings should have stopped flashing, however you are still in the settings menu. Now once again hold the top and bottom buttons down until you get a "P1".
Time for the Chinese English:
*************************************************************************************************************************************************************************************************
S_LCD advanced setup function is only applicable to professional technicians. Advanced option parameters are as
follows：P1_motor characteristics, P2_motor velocity signal pulse, P3_Power-assisted mode, P4_the throttle startup mode,
P5_the power monitoring mode.
1. Enter advanced setup interface
A. The advanced setup is accessible after entering the general setup menu (such as speed-limitation parameter, wheel
diameter parameter, metric or English unit selection).
B. Press the button SW to stop the three common parameters from flashing.
C. Press the button UP and DOWN synchronously for 2 seconds to enter the advanced options setup interface.
2. Set advanced option parameter P1
P1 is motor character parameter, and equals to reduction ratio multiplied by rotor alnico (magnet) number. If decimal fraction
appears, round off first. After entering the advanced setup interface, it is found that if the parameter P1 flashes, you could
use the button UP and DOWN to adjust the P1.
3. Set advanced option parameter P2
P2 is motor velocity signal pulse parameter. After setting the P1,short press the button SW to set the parameter P2. If the
wheel rotates one time, the pulse equals one, then P2 is set as one ,if the wheel rotates one time, the pulse equals six, then
P2 is set as six. If the motor is not equipped with velocity signal outputting function, you could set the PS as 0.
Attention: if P2 is set as zero, the following defects may appear, when the motor stops rotating or the internal rotor rotates
slower than the external rotor, the velocity indicated on the apparatus may be incorrect.
4. Set advanced option parameter P3
P3 is the power-aided mode. If the P3 is set as one, it indicates that the power-aided mode is five-grade torque simulation
mode. If P3 is zero, the power-aided mode is five-grade mode. The setting method is the same as described above.
All the advanced option parameter setup finishes, long-press the button SW to save the settings and exit.
5. Set the Advanced Parameters P4
P4 is the throttle startup mode of. If P4 equals to 1, it indicates a non-zero startup mode of the throttle (that is to say, the
throttle can only be effective after the pedal power starts). When P4 equals to 0, it means the throttle is on zero startup
mode, (that is to say, the motor can be started directly by the throttle).
6. Set the Advanced Parameters P5
P5 is the power monitoring mode. If P5 equals to 0, it indicates that the power monitor is under the mode of "immediate
voltage". In other words, it is a method to judge the battery capacity according to the current voltage of the battery. When P5
equals to a specified parameter, the battery monitor is under the mode of "smart power" (the parameter is determined on the
basis of the battery characteristics, and it is generally among 4-11 for the common 24V lithium, and 5-15 for 36V lithium).
7. Parameter Saving
Long pressing the button SW will save and in the meantime exit the interface of parameter configuration after the
adjustment of the parameter configuration.
*************************************************************************************************************************************************************************************************
On my LCD, P1 is set to 48, while the rest are all set to zero. Those are factory settings. The LCD and Cycle Analyst measured speeds are within 5Kph of each other (mainly due to the LCd only being able to select "20 inch" as the wheel size when the Cycle Analyst can have a more acurate size dialed in (I have a fairly large tyre on the hub motor).
That's all I have my friend, I wish you luck!
Cheers.
