A single-cylinder motorcycle engine, also known as a mono or thumper, is a type of internal combustion engine that uses a single cylinder to convert fuel into mechanical energy. Here's a general overview of how it works:
Intake Stroke: The engine cycle begins with the intake stroke. As the piston moves down, the intake valve opens, allowing a fuel-air mixture or air (depending on whether it's a two-stroke or four-stroke engine) to enter the combustion chamber.
Compression Stroke: After the intake stroke, the piston moves back up, compressing the fuel-air mixture. In a four-stroke engine, both the intake and exhaust valves are closed during this stroke. In a two-stroke engine, the compression occurs simultaneously with the next stroke.
Combustion Stroke: At the top of the compression stroke, the fuel-air mixture is ignited by a spark plug (in a gasoline engine). The resulting combustion creates a rapid expansion of gases, pushing the piston downward.
Power Stroke: The downward motion of the piston during the combustion stroke is called the power stroke. It transfers the energy generated by the combustion to the connecting rod, which in turn transfers it to the crankshaft.
Exhaust Stroke: Once the power stroke is completed, the exhaust valve opens (in a four-stroke engine), allowing the exhaust gases to exit the combustion chamber as the piston moves back up during the exhaust stroke. In a two-stroke engine, the exhaust occurs simultaneously with the next intake stroke.
Repeat: The cycle repeats as the piston continues to move up and down, with each stroke occurring in a specific sequence (intake, compression, combustion, exhaust).
It's important to note that single-cylinder engines have a simpler design compared to engines with multiple cylinders. While they may have fewer cylinders, they are still capable of powering motorcycles efficiently, especially in smaller displacement bikes where simplicity, lightweight construction, and compactness are valued.