What are the symptoms of a loose scooter belt?

[VonReagan]

The timing chain of a scooter, despite its strong durability, is not maintenance-free for life. With engine usage, stress, and wear over time, it will stretch, develop gaps, and result in a loose timing chain. During operation, abnormal noises may occur, and the chain may even skip teeth. In severe cases, it can damage the engine. Below are the main functions of the timing belt: 1. It drives the engine's valve train, ensuring that the intake and exhaust valves open or close at the appropriate times to allow normal air intake and exhaust in the engine cylinders. 2. The timing chain connects the sprockets of components such as the crankshaft and camshaft with high-strength metal chains, keeping them synchronized in operation. 3. Due to the high-speed movement between metal parts, which causes rapid wear and high temperatures, a corresponding lubrication system must be designed for cooling and lubrication.