The crankshaft is the heart of any performance engine and S&S has been perfecting the art for over six decades. Stronger, more durable, and trued to a spec others can only dream of, these crankshaft assemblies for the Milwaukee Eight are the best of the best to build your high performance engine around. Made out of heat treaded 4140 material, harder and more than twice as strong as stock. The stronger assembly eliminates the need to weld the crankpin. The High Strength connecting rods are designed with Finite Element Analysis to eliminate weak spots and handle more power. Consistent balance and precision machining makes them capable of higher RPM and perfect for gear drive cams. Crankshafts that have connecting rods with tapered piston wrist pin ends can be used with stock or S&S pistons. The full-width version can only be used with S&S pistons and S&S Big Bore cylinder kits. Crankshafts with 4 5/8" stroke can only be used with pistons that are designed for this stroke.

4 5/8" stroke gives:
- 113CI from a 107CI engine with stock 3 15/16" bore
- 117CI from a 114CI engine with stock 4 1/64" bore
- 121CI from a 117CI engine with stock 4 5/64" bore
- 131CI with an S&S 4 1/4" Big Bore kit
- 136CI with an S&S 4.320" Big Bore kit