While the pistons are the “muscles” of the engine, the crankshaft and camshaft are the “skeleton” and the “brain.” They work in a precise, mechanical dance—connected by a timing belt or chain—to ensure the engine breathes and moves in perfect sync.

• Main Journals: The central pivot points that sit in the engine block. This is where the crankshaft “rests” and spins.

• Crank Pins (Rod Journals): These are offset from the center. The connecting rods from the pistons attach here. Their “throw” distance determines the engine’s stroke.

• Counterweights: Precisely machined weights opposite the crank pins. They balance the rotating mass to prevent the engine from vibrating itself to pieces at high RPM.

• Oil Passages: Drilled holes throughout the shaft that allow pressurized oil to reach the bearings.