Allows for easy start by initially reducing crank compression, but once the engine starts and rpm increases, the compression release lobe is centrifugally retracted and the engine runs normally, with full compression, and without any loss in performanceOptimized for 88''/96''/103'' to 106'' Touring bike with slip-on mufflers and 9.0:1 to 9.0:9 compression with stock starterBolt-in for stock or mildly modified Touring modelsGreatly improves low-end and midrange torqueStrongest from idle to 4000 rpmIncludes camshafts, gearcover gasket, bearings, retaining ring, o-ring, threat lock and instructions Made in the USANot recommended for compression ratios of 10.0:1 or greater.Installer must check coil bind, valve-to-valve clearance and valve-to-piston clearance.Not for models with OEM compression releases.Can be used with stock pushrods, lifters, and springs (unless noted).