What differs in a 4-stroke engine
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The 4-stroke engine is well named for it's 4 different cycles within one power stoke (2-rotations)
1. We will start with the piston at the top of the cylinder, nearest the spark plug. Know as the Intake Stroke, the piston descends the cylinder reducing pressure and the fuel-air mixture is forced into the cylinder through the intake port.
2. With the intake and exhaust valves closed, the piston returns to the top compressing the mixture. This is known as the Compression Stroke.
3. After compression we need ignition, at the precise moment the spark plug ignites the mixture propelling the piston down. This is known as the Power Stroke.
4. The final stroke is the Exhaust Stroke. The piston returns to the top of the cylinder evacuating the spent fuel-air mixture.
With these four steps we have the the simple makings of a 4-Stroke Internal Combustion Engine.
All vehicles are governed by Newtons second law, F=MA.
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