What Happens If the Valve Clearance of a Scooter is Too Large or Too Small?
1 Answers
The intake and exhaust valve clearance of a motorcycle is approximately 0.05 millimeters. When the engine is running, the valves will expand due to the increase in temperature. If there is no gap or the gap is too small between the valve and its transmission components in a cold state, the thermal expansion of the valve and its transmission components in a hot state will inevitably cause the valve to close improperly, resulting in air leakage during the compression and power strokes of the engine. This leads to a decrease in power and, in severe cases, even difficulty in starting. The valve will expand due to the increase in temperature. If there is no gap or the gap is too small between the valve and its transmission components in a cold state, the thermal expansion of the valve and its transmission components in a hot state will inevitably cause the valve to close improperly, resulting in air leakage during the compression and power strokes of the engine. This leads to a decrease in power and, in severe cases, even difficulty in starting. To eliminate this phenomenon, a certain gap is usually left in the valve and its transmission mechanism during cold assembly of the engine to compensate for the expansion of the valve after heating. This gap is called the valve clearance. Here is additional information about the intake and exhaust valve clearance of a motorcycle: The standard for the intake and exhaust valve clearance of a motorcycle is not fixed, as it varies from one motorcycle to another. The size of the intake and exhaust valve clearance may be the same or different. Since the valve train operates at high speed and high temperature, components such as the valve tappet and valve stem will elongate when heated, automatically pushing the valve open. This causes the valve and valve seat to close improperly, resulting in air leakage.
