Beehive valve spring kit TC05-17 .610" l

Fits 2004-2022 Evolution Sportster and 2005-2017 Twin Cam, Complete kit for use up to .610" valve lift. Includes chrome silicon springs, steel retainers, steel lower collars, stock style valve keepers and Viton valve stem seals

By taking advantage of the latest development in valve spring wire chemistry and manufacturing techniques, Kibblewhite Precision Machining Inc., in short KPMI, has developed ovate wire "Beehive" style springs that will live and perform at a high level in Harley-Davidson applications. By coupling these developments with strict KPMI design, simulation and analysis protocols, they were able to overcome the torsional stresses unique to ovate wire springs that previously severely limited their operating parameters. This was critical, as there are nearly 100 camshaft part numbers available for these applications. Springs are progressively wound using Kobe Super-Clean chrome silicon based wire that is heat treated and shot peened. KPMI uses its tightly toleranced, FEA designed hardened steel Posi-Loc style retainer in these applications to insure correct assembly height and resist keeper "pull through". Kits also include hardened steel base washers to locate the spring and control lateral movement. Kits are great for stock and moderate performance rebuilds and reduce total valve train mass for longevity.