Jims M10x1.0 compression release valves

These Jims release valves make starting your engine effortless by venting cylinder compression with just the push of a button. This is a good alternative for Heavy Duty starter motors and high amp batteries on any Sportster, Buell or Big Twin. The heads have to be drilled and tapped with 10mm thread. Use the ZPN750314 fixture guide tool to install these compression release valves in Twin Cam cylinder heads. Jims compression release valves are sold in sets of 2.