Designed for engines with 96 to 106 CID and 9:1 to 9:9 compression, this is a bolt-in cam set for stock or mildly modified touring bikes. Reverses the rear cam's direction of rotation, providing additional operating clearance between cam lobes making higher cam lifts possible. More power across the rpm range, with improved low and midrange torque, strongest from 1,000-4,000 rpm. Increases valve timing accuracy by eliminating timing chain lash and loosely fit stock chain. Material must be removed from inner surface of the stock gear cover to install. A hydraulic press and other professional level tools are required for installation. Cam bearings and gaskets must be replaced when installing new cams. S&S recommends that adjustable pushrod/cover kit be used. Not recommended for compression ratios of 10:1 or greater. Kit includes inner gears, outer gears, inner and outer bearings, gaskets and instructions. Made in the USA. Installer must check coil bind, valve to valve clearance, and valve to piston clearance.. Due to the inherent characteristics of gear drives, you may experience more valve train noise..