What Causes the Low-Speed Rattling Noise in a Scooter?

[LaReese]

Scooter low-speed rattling noise can be caused by the following reasons: Faulty piston in the lower caliper: If the piston is stuck, it may prevent the brake shoes from fully separating from the disc, leading to a squeaking sound. The piston can be disassembled and cleaned. Worn disc brake shoes: If the brake shoes are worn (including uneven wear, which could also be caused by the aforementioned piston issue), and the friction surface edges expose metal, they will squeak when rubbing against the disc. Uneven disc surface: If the disc shows obvious concentric groove marks and is no longer a smooth friction surface, these marks indicate uneven wear on the brake shoes.