Connecting Rod: Description and Operation

Pistons and connecting rods
Each of the aluminum alloy pistons has two compression rings and an oil control ring. The pistons are secured to the connecting rods by semi-floating gudgeon pins. Each gudgeon pin is offset by 0.5 mm (0.02 inch). The top of each piston is recessed, the depth of recess determining the compression ratio of the engine. Plain big-end bearing shells are fitted to each connecting rod and cap.