When a motorcycle shakes or vibrates while stationary and the engine is running, it can be attributed to a few factors:
Engine vibrations: Motorcycles typically have high-revving engines, which can produce significant vibrations. These vibrations are transmitted to the frame and other components of the motorcycle, leading to the sensation of shaking. Some motorcycles, especially those with large displacement engines or single-cylinder configurations, tend to vibrate more than others.
Idle speed: The idle speed of the engine, which is the rotational speed of the engine when it is at rest, can affect the level of vibrations. If the idle speed is set too low, it can result in uneven running and increased vibrations.
Mechanical issues: Certain mechanical issues can cause excessive vibrations. These can include worn-out engine mounts, loose or misaligned components, damaged or unbalanced wheels, or a faulty drivetrain. If there are any issues with these parts, they can contribute to the shaking of the motorcycle.
Fuel system problems: A malfunctioning fuel system, such as a clogged or dirty fuel injector, can disrupt the smooth operation of the engine, resulting in vibrations.
Poor maintenance: Inadequate maintenance practices can lead to increased vibrations. Lack of regular servicing, including engine tuning, oil changes, and general upkeep, can contribute to the shaking of the motorcycle.
It is worth noting that some level of vibration is considered normal for motorcycles. However, if the shaking is excessive or accompanied by other concerning symptoms such as strange noises or loss of power, it is advisable to have the motorcycle inspected by a qualified mechanic to identify and address any underlying issues.