Fits into existing 5-speed cases lowers the rpm at cruising speeds6-speed gear set (3.24:1 1st gear/.86:1 6th gear), 28-tooth motor sprocket, longer primary chain, adjusting shoe, fixed spindle-shift drum and anti-overshift ratchet shift pawl assemblyAll gears are full-width Baker ground gears 4th, 5th and 6th gears are helical for silent operationIncludes easy-to-follow instructionsBearing door is manufacturered from 6061-T6 Aluminum and features wider bearings and a bearing retainer plates instead of the stock style snap ringsRedundant Neutral Smooth Shift SystemGearsets are made out of 8620 steel, gears are cut before heat treating then precision ground with a diamond coated tooling for quieter operation. Made in the U.S.A.