ZIPPERS PERFORMANCE THUNDERSPORT CYLINDER HEADS HARLEY M8 GEN 2 HEAD OPTION:STAGE 2 4-1/8" x 4-1/8" bore and

4-1/8" x 4-1/8" bore and stroke

Black powder coated brackets (application specific fork clamps sold separately)

● 304 Stainless Steel Construction

0165” wall one piece pushrods or factory one-piece pushrods

install can be performed with engine still in frame

ZIPPERS PERFORMANCE THUNDERSPORT CYLINDER HEADS HARLEY M8 GEN 2 HEAD OPTION:STAGE 2 4-1/8" x 4-1/8" bore andZIPPERS PERFORMANCE THUNDERSPORT CYLINDER HEADS HARLEY M8 GEN 2 SELECT LEVEL OF HEADWORK IN OPTIONS THESE ARE AN EXCHANGE ITEM STAGE 2 Zippers Gen2 Stage 2 head upgrade begins with an inspection of the cylinder head as received; seats, guides and valves are all inspected for unusual wear or issues. After the inspection is completed, the valves and seats are professionally machined and blended to provide maximum flow in an un ported head to achieve