I have a new 2015 RZR 900S and its really new less than 5 miles and it rattled really bad upon start up after setting for a few weeks. So like everybody else I started to look for cam chain tensioners. I settled on the Boondocker tensioner. So I took the plunge and ordered the Boondocker and payed my $200.00. When the tensioner arrived I removed the stock unit and tried to screw in the Boondocker adapter and it hit the starter motor and would not screw all the way in. I had read here on the forum that some of the guys had sanded the edges of the adapter to make it fit. I did not want to accept the liability of altering a manufactures part. So I called Pete at Boondocker and advised him I was returning the tensioner. He asked if I could wait and that he would send me a modified part and would I try that before returning the tensioner, no problem. The modified part arrived and it fit perfectully. It took about 30 minutes to install the tensioner and it works great. no more rattle. I would like to say that pete and the whole staff at Boondocker were great to work with. It seems that the 900S has a different starter than the 1000 or the other 900 that was the issue. :clap: