Electric bikes can be equipped with a torque sensor and/or a cadence sensor to measure the rider's input and provide electric assistance.  They have some similarities but also major differences in how they work and are helpful for electric bike riders.

Torque Sensor

A torque sensor measures the force applied to the pedals and gives electric assist accordingly. When a rider applies more force to the pedals, the torque sensor sends a signal to the motor to provide more assistance, making it easier to pedal. When the rider applies less force, the sensor sends a signal to the motor to reduce the level of assistance.

This system allows for a more natural and intuitive riding experience, as the level of assistance is directly related to the rider's effort. It can also increase the efficiency of the electric motor, as it only provides assistance when needed. The major benefits of a torque sensor electric bike are a more natural ride feel, more efficient use of battery and motor, and better control and safety.

The torque sensor is commonly used in mid-drive electric bike systems, but also can be used in other types of e-bikes. Torque sensors are generally more expensive than cadence sensors.

Cadence Sensor

The cadence sensor is typically a small sensor that attaches to the bike's frame or cranks and detects the rotation of the pedals. The sensor sends a signal to the electric motor, which then provides assistance to the rider based on the pedaling rate. This means that the electric assist will be more consistent, regardless of the rider's effort.  This allows the rider to maintain a consistent pedaling rate, even when riding uphill or against a headwind.

Cadence sensors are often paired with other types of sensors, such as torque sensors or speed sensors, to provide a more complete and accurate picture of the rider's effort. They can also be used to fine-tune the assistance provided by the electric motor, making the ride feel more natural and intuitive.

One of the benefits of using a cadence sensor is the ability to control the assistance level more precisely. It also can improve the overall bike efficiency, as the motor will be providing power only when the rider is pedaling. However, it should be noticed that the cadence sensor system may not be as responsive as the torque sensor system, as it only measures the pedaling rate and not the torque applied by the rider. Cadence sensors are generally less expensive than torque sensors.‍

Combining Cadence and Torque Sensors

A cadence sensor and torque sensor can be combined on an electric bike to provide a more complete and accurate measurement of the rider's effort.

When used together, the cadence sensor measures the pedaling rate or cadence of the rider, while the torque sensor measures the amount of force or torque applied to the pedals. This information is then used to adjust the level of assistance provided by the electric motor, providing a more natural and intuitive riding experience.

The combination of these sensors allows the bike to adjust the level of assistance based on both the rider's pedaling rate and the amount of force they are applying to the pedals. This can make the ride feel more natural and responsive, and can also increase the efficiency of the electric motor.

It's worth noting that some e-bike systems may use both sensors in different ways to optimize the assistance provided. For example, the torque sensor can be used to provide a more responsive and natural feeling while the cadence sensor can be used to optimize energy consumption.

Overall, combining cadence and torque sensors can provide a more accurate and efficient measurement of the rider's effort, which in turn can lead to a better riding experience.

What is Best For Your Electric Bike?

Ultimately, which type of sensor is better for an electric bike depends on the individual rider's preferences and needs. Torque sensors offer a more natural and seamless ride experience, but they are generally more expensive. Cadence sensors are less expensive, but the electric assist may feel less natural and responsive.