Answer: Piston.
Crankshaft.
Camshaft.
Spark plug.
Cylinder.
Valves.
Carburetor.
Flywheel.
Explanation: What Are the Strokes of a 4-Cycle Engine? At the end of the compression (previous) stroke, the spark plug fires and ignites the compressed air/fuel mixture. This ignition/explosion forces the piston back down the cylinder bore and rotates the crankshaft, propelling the vehicle forward.
