How does a 4 stroke dirt bike engine work

A 4 stroke dirt bike engine works on a principle of four strokes or four cycles of a piston. There are two upward strokes and two downward strokes that make up the four strokes. These four strokes are called the intake stroke, the compression stroke, the combustion stroke and the exhaust stroke. On the intake stroke, the intake or fuel valves are opened to let an air-fuel mix into the combustion chamber. On the exhaust stroke, the exhaust valves are opened to let out the burnt fuel or exhaust created from the combusted fuel