Petrol engines are more often used in motorcycles, due to their simplicity. To know more about the reason why petrol engines are used in bikes refer to.
Almost all engines of this generation are Four-stroke engines,Two-stroke engines are almost faced out due to their inefficient operation.
Four stroke petrol engine
Before going to 4 stroke engines , let’s take a view about what is aStroke????
Stroke is the distance traveled by a piston from TDC (top dead center) to BDC (bottom dead center)and vice versa, during a stroke the crankshaft will rotate 180′.
A four stroke petrol engine follows Otto cycle. Since there are four strokes , a working cycle will be completed in 4 strokes, ie 720, revolution of crankshaft.
During intake stroke ,air fuel mixture is taken through inlet valve. during this time the exhaust valve remains closed.Piston moves from TDC to BDC.
Both the valves are closed and piston moves from BDC to TDC ,this compresses the air fuel mixture. During compression pressure and temperature rises.
Valves remain closed ,At the end of compression stroke ,the fuel is ignited by a spark.Combustion of fuel increases pressure in cylinder and the mixture expands pushing the piston to BDC. (only in power stroke engine delivers power ).
Exhaust stroke –
During exhaust stroke , the exhaust valves open and the piston moves from BDC to TDC pushing all the waste gas out through exhaust valve.
“The power to execute Intake ,compression ,Exhaust stroke comes from Flywheel.