What Causes the Abnormal Noise After a Motorcycle Shuts Down?
1 Answers
Here are the specific reasons for the abnormal noise after a motorcycle shuts down: 1. Thermal Expansion and Contraction: The abnormal noise is caused by the thermal expansion and contraction of the engine. When the motorcycle engine is running, the temperatures in different parts vary. The cylinder block temperature typically does not exceed 100°C, the exhaust pipe temperature can generally reach around 400~500°C, and the three-way catalytic converter temperature can be as high as 600°C. As a result, the expansion rates of different parts are not uniform. After the motorcycle shuts down, the engine stops working and gradually cools down due to the ambient temperature. 2. Abnormal Noise from the Three-Way Catalytic Converter: The three-way catalytic converter usually has a ceramic core. During cooling, the contraction of the ceramic does not synchronize with the metal, which may also produce rhythmic abnormal noises.