A tappet noise in a motorcycle, often referred to as "tappet chatter" or "tappet ticking," typically occurs due to a few common reasons:
Incorrect Valve Clearance: Tappets, also known as valve lifters, are responsible for maintaining proper clearance between the camshaft lobes and the valves. If the valve clearance is too tight or too loose, it can result in a tapping or ticking noise. This can happen over time due to wear or incorrect adjustment of the valves.
Worn or Damaged Tappets: Tappets can wear out or become damaged over time, leading to increased clearance or poor functioning. As a result, they may produce noise when they are not functioning properly.
Insufficient Lubrication: Adequate lubrication is crucial for the smooth operation of tappets. If there is insufficient oil reaching the tappets due to low oil level, oil blockages, or a malfunctioning oil pump, it can result in increased friction and noisy operation.
Engine Overheating: High temperatures can affect the performance of tappets. If the engine is consistently overheating or operating at excessively high temperatures, it can lead to tappet noise.
Engine Wear: As the engine components age, including the tappets, they may experience wear and tear. This can contribute to increased noise levels.
To address tappet noise, it is recommended to consult a professional motorcycle mechanic. They can inspect the tappets, check the valve clearance, and identify any worn or damaged components. Adjusting the valve clearance, replacing worn tappets, ensuring proper lubrication, and addressing any underlying issues should help reduce or eliminate the tappet noise.