The Fatfish Biggie Speed Sensor is the genuine replacement part that keeps the pedal assist system on your Biggie working as it should. Mounted on the frame near the wheel and crank, the sensor reads the movement of the wheel magnet and sends speed data to the controller. This allows the motor to deliver smooth and consistent pedal assist based on how fast you are riding.

If your pedal assist feels unresponsive, cuts in and out, or has stopped working, a faulty speed sensor is often the cause. Replacing it restores accurate communication between the motor and controller, bringing back the seamless assistance the Biggie is known for.

Built for durability and designed to fit the Fatfish Biggie, this sensor comes ready with its connecting cable for straightforward installation.