This big bore cylinder and piston kit can be used as replacement for the cylinders and pistons for an S&S Cycle V107 engine or as the basis for a new engine build. Kit contains S&S Cycle 4" bore cylinders and forged pistons, rings, wrist pins, head and base gaskets. The cylinders are machined and are intended for use in S&S Cycle Special Application crankcases 1984-99 big twins. This kit must be used with 4-1/4" stroke flywheels resulting in 107" displacement. Cylinder finish is natural aluminum. This cylinder kit must be used with S&S cylinder heads with the S&S bolt pattern. For best performance, appropriate camshafts, performance air cleaner, performance exhaust and fuel system tuning are required.