Four-stroke engine with a wide range of use, four-punch engine that is, the pistons every four times reciprocating motor cylinder point fire, the specific principle of work as follows:
1. Air inlet: At this time the inlet door opens and the piston is down, and the mixture of gasoline and air is sucked into the cylinder.
2. Compression: At this time the inlet door and exhaust valve are closed at the same time, piston uplink, mixed gas is compressed.
3. Combustion: When the mixer is compressed to the minimum, the spark plug ignites the mixture, the pressure of combustion pushes the piston down and drives the crankshaft to rotate.
4. Exhaust: When the piston down to the lowest point when the exhaust door open, exhaust gas discharged, the Pistons continue to uplink the excess exhaust gas out.