ARC Billet Cranks are machined from the hardest, toughest material ever used for small, 4 stroke engines. Features a true, 1/8" journal radius for strength and durability. Also features airplane wing style counter weights that are proportionaly designed for superior balance. This crank is balanced for a three inch bore. It uses a 7/8" journal. ARC Billet Crankshaft .563" X 3.00" * 3" Bore X 3" Stroke = Balanced with Cam Clearance