A couple years ago I had an arctic cat ZR cross country. I bought the klymaxx seat wedge to try with it. I was not impressed. It didn't mount up very well and it didn't work very good. I was constantly sliding forward towards the gas tank. I was amazed at how much your center of gravity went up and it made for quite a tippy ride. Also when sidehilling it was very hard to slide down on the side of the seat to shift your weight onto the side. I took it off after about a week of riding. It did make it easier to transition from sitting to standing but I got real tired of constantly pushing back with my legs to keep from sliding forward. Just my $.02 but like I said it was not on a viper.