What Causes Abnormal Noises in Motorcycle Engines?

[McDallas]

Abnormal noises in motorcycles are mainly caused by the following factors: 1. Temperature: Some engine noises appear as the temperature rises, while others diminish with increasing temperature. Some noises are often accompanied by heating phenomena, so in addition to listening to the noises, it is also necessary to measure the temperature to aid in diagnosis. 2. Speed: The noises have a certain relationship with the engine speed and vehicle speed. Generally, when diagnosing engine noises, the throttle is frequently adjusted, and when diagnosing transmission system noises, the speed is continuously changed. This is because some noises are more severe at high engine speeds, some are more noticeable at low speeds, and others are more prominent at medium speeds. 3. Load: Load affects the noises, with noises generally increasing as the load increases. However, there are exceptions. 4. Lubrication: Regardless of the type of noise, poor lubrication conditions usually make the noises more severe.