Basic composition of motorcycle

Motorcycle is composed of five parts: engine, transmission system, walking system, steering, braking system and electrical instrument equipment. The overall structure of the motorcycle and the name of each component.

Engine
1. Characteristics of motorcycle engine
(1) The engine is a two-stroke or four-stroke gasoline engine.
(2) the use of air cooling, there are two kinds of natural air cooling and forced air cooling. General models adopt a natural air-cooled cooling method that relies on air blowing through the cylinder head and the heat sink on the cylinder liner to take away heat during driving. In order to ensure the cooling of the engine before driving at a low speed and before starting, the high-power motorcycle engine adopts a forced air-cooling cooling method that is equipped with a fan and a wind deflector, and uses forced air to blow the cooling fins.

2. The Body
The engine block is composed of three parts: cylinder head, cylinder block and crankcase. The cylinder head is made of aluminum alloy with cooling fins. The new four-stroke motorcycle engine adopts overhead valve, chain drive, and overhead camshaft structure. The cylinder block material is mostly bimetal (cast aluminum heat sink outside the wear-resistant cast iron cylinder liner) to obtain better heat dissipation effect.

3. Crank connecting rod
The crankshaft of the motorcycle engine adopts a combined type, which is formed by pressing the left half crankshaft, the right half crankshaft and the crank pin. Ball bearings are installed on the main journals of the left and right half shafts to support the crankshaft on the crankcase. The two ends of the crankshaft are respectively equipped with a flywheel, a magneto and a clutch driving gear.

4. Carburetor
The carburetor is an important part of the motorcycle fuel supply system, located between the air filter and the engine intake. Generally, motorcycle engines use a flat suction air flow direction, a plunger throttle valve, and a float chamber carburetor. The structure of the carburetor is mainly composed of two parts: the float chamber and the mixing chamber. The float chamber is located under the carburetor, and an oil pipe is connected to the oil tank through the throttle switch. Through the needle valve on the float, the oil level in the float chamber is maintained at a certain height to stabilize the oil supply pressure. The function of the mixing chamber is to mix gasoline evaporation and atomization with air, so that the engine can obtain the required mixture under various loads and speeds. It is composed of a throttle valve, an injection needle, an injection pipe, a gas and an oil passage, etc.