Cant reach max speed

I have a 2015 rzr 900s and I am only able to reach about 60-65ish. I had this problem before and finally figured it out and my home dealer had to completely replace the primary clutch and when I got It home it ran great and reached the max speed of 72mph no problem. But this last weekend my buddy and I went out riding in the snow a bit and we were messing around and he has the same rzr and he blew me away. It has power just seems at about 50 it looses it and doesn’t want to go much faster than 60 but the rpms are still hitting the 8000 something range. Could it be my clutch again? Thought it could of been wet belt or something but put it inside heated shop all night to dry and same thing the next day. Any thoughts? Thanks