Compression Release Valves

4 products

Compression Release Valves for Harley-Davidson covers the actual valves fitted into the cylinder head, suiting 1999-2017 Twin Cam engines, 1984-1999 Evolution Big Twin, Sportster, Buell XB and various other Harley-Davidson applications. Iron City Motorcycles is an authorised Harley-Davidson dealer in Leeds, and we stock valves from Kibblewhite — a premium US manufacturer famous for precision valvetrain components — and Jims, another name synonymous with quality Harley-Davidson engine parts. Compression release valves open at low cranking speed to vent cylinder pressure and let the starter spin a high-compression Harley-Davidson engine over cleanly. A failed valve means hard or impossible starting, so fitting proper replacements from a trusted source is essential. Browse the full range below.