16770-84-A Evo cylinder head & base gasket kit

This James Gaskets cylinder head and base gasket kit is a versatile solution for 3-1/2 inch bore engines, fitting 1984 to 1999 Evolution Big Twins and 1988 to 2022 Sportster 1200 models, excluding the XR1200. It is a complete kit to service one engine, featuring 0.045-inch head gaskets and 0.030-inch base gaskets. To ensure a perfect fit regardless of your specific year, James includes both Type A and Type B base gaskets. This covers the slight perimeter differences between early Big Twin and later Sportster styles, ensuring the gasket follows the cylinder contours perfectly. Sold as a kit, it includes the necessary o-rings for oil returns.