For years the British motorcycle industry has been plagued with very low quality valve springs, especially for A50 & A65 unit twins… Luckily CBS was able to get Kibblewhite to make a quality and comprehensive spring kit for our unit twins 

This spring kit we are offering is new for 2023 – “lightweight” kit comes included with everything as pictured from (8) keepers, (4) top retainers, (4) bottom base washers & (8) springs 

This kit is perfect for street applications and mild racing applications paired with standard / mild lift cams… – made proud in the USA. Works will all BSA unit twins including the following models: Royal Star, Lightning, Firebird, Spitfire, Spitfire, etc from 1962-1972.