Installed on a 2018 xp1k rzr, should have done this upgrade years ago. If you are dealing with the high pitch noise at certain speed in low range and high this is the fix. This secondary is 100% noise free, I got the secondary with the engine brake helix which is just slight enough to assist on downhill deceleration, to a certain speed. We rode for 6 hours yesterday and was one of the most enjoyable rides I've had in this machine since purchase. I didnt find myself the first time wanting to trail ride in high range to try and get away from the noise of the previous secondary, which has costed me enough money in belts and primary wear to pay for this secondary. Dont believe the hype of band aid fixes, thicker belts, clutch shims etc, been there done that. Spend the money once and never look back. Thanks for offering a great product and fast shipping as always.