What are the reasons for the loud sound of a motorcycle exhaust pipe?

[SavannahRose]

Motorcycle exhaust pipe sounds loud due to the internal muffler structure design and the large exhaust pipe outlet. The principle of exhaust pipe noise reduction: The motorcycle exhaust pipe reduces noise as the airflow from the engine passes through perforated pipes and baffles inside the muffler, repeatedly circulating until the noise gradually attenuates. The intake valve opens, the piston moves downward, drawing the air-fuel mixture into the cylinder; both the intake and exhaust valves close, the piston moves upward, compressing the mixture; when the mixture is compressed to its minimum, the spark plug ignites it, and the resulting combustion pressure pushes the piston downward, rotating the crankshaft; when the piston reaches the lowest point, the exhaust valve opens, expelling the exhaust gases, and the piston continues upward to expel any remaining exhaust. Precautions for motorcycle riding: Avoid racing with cars, drive safely according to traffic regulations, and yield to pedestrians. Do not follow too closely; maintain an appropriate distance behind the right rear corner of the vehicle ahead. When overtaking, pass from the left side of the vehicle in front; avoid overtaking from the right or between two parallel vehicles.