Need a matched pair of performance cylinder heads?  These may be just the ticket.  They are brand new, not reconditioned.  Improved cylinder head design comes with extra fin for maximum cooling and strength.  They feature 40mm x 35.5mm stainless steel valves, single high-rev valve springs, and improved chamber design for maximum flow, 12mm long-reach (3/4") spark plug holes for much improved resistance to stripping or cracking,  and fully sealed rocker blocks so they don't require o-rings for the rockers.  These are cut for 94mm cylinders (or thick-wall 92's). 54cc ccombustion chambers. Sold in pairs.