Yamaha Magnet to Sensor Speed

The Yamaha speed sensor system operates by detecting either a magnet or a rotor with fixed magnets, which are recognized by the sensor located on the rear frame rail. The sensor sends data to the motor/controller to regulate speed and control motor assistance. Types of magnets used: Bearing magnet: The most popular type; it is securely clamped or screwed into a rear wheel housing. Rotor brake disc magnet: In some models, a magnet is integrated into the rotor brake discs, providing a clean appearance and reducing breakage. Integrated magnet (rear): In some new bicycles, the magnet is integrated into the rear wheel or rear axle, although this is still model-specific. Replacement options: You can purchase the Yamaha OEM speed sensor magnet.