(2) Air-cooled cooling is adopted, and there are two types of natural air cooling and forced air cooling. The general model adopts the natural air cooling method that relies on the air blowing through the cylinder head and the radiating fins on the cylinder liner to take away the heat during driving. In order to ensure the cooling of the high-power motorcycle engine before driving at a low speed and before starting, it adopts a forced air-cooling method with a fan and a wind deflector, and the use of forcedly introduced air to blow the cooling fins.

 

(3) The engine speed is high, generally above 5000 rpm. The power per liter (effective power per liter of engine displacement) is large, generally around 60 kilowatts/liter. This shows that the degree of strengthening of the motorcycle engine is high, and the engine size is small.

 

(4) The engine crankcase is integrated with the clutch and gearbox, and the structure is compact.