The torque sensor in an electric bike is one of the most important parts that affect the performance of the bike because it is responsible for delivering the signal to the control unit and then to the motor to give you a force proportional to the pressure of your feet on the crank.
In this post, I will share with you a complete information guide about the torque sensor in the electric bike.
We will discuss the types of torque sensors and their method of operation, in addition to the method of installing each of them, in addition to the test method.
Finally, we will take a quick look at the torque sensor setup on the electric bike controller screen.
How to know if you have an issue with the torque Sensors?
in order to test the torque sensor, you will need special tools to measure the response of the sensor to pressure on it, but there are signs that you can notice that indicate a malfunction in the torque sensor, which in most cases is resolved by changing the sensor.
1- Slow start of the bike:
When the torque sensor is working efficiently, there will be no delay in the movement of the bike. As soon as you press the pedal, you will feel the help of the motor, but if you notice a delay in the movement of the bike, even for one second, this means that the sensor does not respond correctly.
2- Sudden stop:
One of the most common signs that there is a problem with the torque sensor is the momentary stopping of the ebike when pedaling (you will feel as if someone is pulling you back) and the reason for this is that the sensor does not send the signal in proportion to the pressure of your feet on the crank.
3- Loudness of the motor.
If you notice a constant increase in the sound of the motor at medium or small speeds while switching, this means that the motor is working hard at medium or small speeds because the torque sensor did not send it a signal to use a force greater than its current strength.
To summarize how to know if there is a problem with the torque sensor.
As a general rule, if you find a delay in the movement of the ebike or a momentary pause while using the pedal, or the loudness of the motor sound at small or medium speeds while pedaling this means that the torque sensor does not work efficiently.
What Are the main types of Ebike torque sensors?
As a general rule, there are two types of ebike torque sensors first is the Strain Gauge Sensor which is also known as the rear torque sensor, and the hall-effect sensor which is known as the bottom bracket sensor.
1- Rear Torque Sensor (Strain Gauge)
The idea of the rear torque sensor is that whenever the pedal is pressed, the strain Gauge is moved, and based on this movement, a signal is sent to the motor to extract an amount of force equal to the amount of pressure.
In general, this type is considered the least effective of the two types
2- Bottom bracket sensor (hall-effect) How does it work?
The bottom bracket sensor reads the magnetic field around the metal shafts between cranks this happened when the rider stresses the cranks it takes the changes in the magnetic and convert them into voltage signal then send them to the controller
How To Replace Ebike Rear Torque Sensor?
In this part of the post, we will learn how to change the rear torque sensor, and the good thing is that the method of changing is not difficult at all, whether it is in terms of replacment or the tools used.
Allen Key 5mm
Steps for Replacing Rear Ebike Sensor:
1- Remove the rear wheel & the battery
2-Losen the polt attached to the derailleur
3- Gently place the derailleur to avoid any misalignment
4-Losen the three bolts holding the torque sensor
5-Unplug the old torque sensor.
6-put the new torque sensor (make sure not to tighten the fist bolt too hard)
7-tighten the three bolts as much as you can.
8-Put the derailleur back and tighten it well
9-put the rear wheel back
How To Replace Ebike Torque Sensor (Bottom bracket)
In this part of the post, we will explain the steps for replacing the torque sensor (Bottom Bracket)
1-Allen Key 8mm
2-Allen Key 5mm
3-Torque Sensor Wrench
5-Crank removal tool (sleeve 14)
6- Bottom bracket Socket tool
Torque sensor replacement steps.
1- Remove the battery.
2- Remove the left crank by using Allen key 8mm then Use the crank removal tool then wrench 16.
3- Remove the chainring set
4-Remove the right crank by using Allen key 8mm then Use the crank removal tool then wrench 16.
5-Remove the bottom bracket using the bottom bracket removal tool.
6- loosening the new torque sensor.
7- Install the right cup threads using the torque sensor wrench.
8- Install the left cup threads using the torque sensor wrench.
9- Install the wire ring & make sure to place it in the correct area.
10- Install the rooter part of the torque sensor & tighten it using the bottom bracket tool.
11- Reinstall the left crank.
12- Reinstall the chainring set.
13- Reinstall the right crank.
14-Add the battery to the ebike.
15-Plug the torque sensor into the controller.
How to check the Torque sensor setting on Ebike screen?
The last step after installing the torque sensor is to check the settings.
The goal of checking the settings is to make sure that the sensor was installed correctly.
To make sure that the sensor is installed correctly, go to the PAS settings in the controller display and make sure that the current
voltage without using the pedal is 1.5 volts.
If you find the value less than this, you did not connect the cable correctly and you should double-check it.
You can see the following posts for more information about ebike PAS
Ebike Cadence VS Torque Sensor The Difference & How To Use
Ebike Pedal Assist Vs Ebike Throttle- A Practical Comparison