What is the displacement requirement for motorcycles on highways?

[Jan]

Motorcycles with a displacement of 50cc or above are allowed on highways. Below is relevant information about motorcycles: 1. Basic components: Motorcycles consist of five main parts - the engine, transmission system, running gear, steering and braking systems, and electrical instrumentation equipment. 2. Working principle: Four-stroke engines are widely used. In a four-stroke engine, the piston completes four reciprocating movements for each ignition in the cylinder. During this process: the intake valve opens as the piston moves downward, drawing the air-fuel mixture into the cylinder; both intake and exhaust valves close while the piston moves upward to compress the mixture; when maximally compressed, the spark plug ignites the mixture, with combustion pressure driving the piston downward and rotating the crankshaft; as the piston reaches its lowest point, the exhaust valve opens to release waste gases, and the piston continues upward to expel remaining exhaust.