Piston

Components of a typical, four stroke cycle, DOHC piston engine. (E) Exhaust camshaft, (I) Intake camshaft, (S) Spark plug, (V) Valves, (P) Piston, (R) Connecting rod, (C) Crankshaft, (W) Water jacket for coolant flow.

Piston and connecting rod

A piston is a component of reciprocating engines, pumps and gas compressors. It is located in a cylinder and is made gas-tight by piston rings. In an engine, its purpose is to transfer force from expanding gas in the cylinder to the crankshaft via a piston rod and/or connecting rod. In a pump, the function is reversed and force is transferred from the crankshaft to the piston for the purpose of compressing or ejecting the fluid in the cylinder. In some engines (two-strokes), the piston also acts as a valve by covering and uncovering ports in the cylinder wall.

Oversize pistons

• 1st => std.
• 2nd => 0.25mm
• 3rd => 0.50mm
• 4th => 0.75mm
• 5th => 1.00mm