This 4-1/8" stroke 8-1/2" diameter flywheel assembly is a replacement for the flywheels in S&S T111 engines for 2007-'16 big twin models. It also fits 2007-'16 HD® big twin engines, when not using stock pistons, and S&S® T111 engines. Wrist pin ends of connecting rods are full width. Sprocket shaft does not have a stock style bearing race pressed on. This flywheel assembly is for crankcases with Timken® sprocket shaft bearing.