These hydraulic lifter cams are capable of 6000-plus rpm with stock springs and no valve float. Bolt-in cam for heavier touring bikes and high-geared bikes with 65-tooth rear pulleys. Uses stock springs; works with carbs or fuel injection. Crisp throttle response and strong pulling power from 1500 to 6000 rpm. Works well in higher altitudes. Must check coil bind, valve-to-valve clearance and valve-to-piston clearance.. Made in the U.S.A..