This sensor connects directly to the motor's yellow output and automatically cuts motor assistance during gear changes, preventing the chain from hitting the chainrings. A perfect complement to our kits, it effectively protects your derailleur by cutting off the motor at the right moment. Caution: if your derailleur cable is damaged, prefer the version fitted with a cable, as the cable must pass through the sensor, and a frayed cable would prevent correct operation. Ensure the longevity of your drivetrain with this simple and effective solution.