I have a 2005 rxp with a Riva Stage 1 kit that I bought recently. I just took the supercharger in to get rebuilt and the mechanic said it only needed the metal clutch washers but he checked the slip etc and adjusted it. I also changed the oil (level half way between the lines on dipstick), spark plugs, and put in new wear ring. For the first time today i tested the ski in super flat water with a gps, my top speed was 68.4. The water was pretty warm and weather was around 92 degrees. Is it this speed normal for a stage 1? I thought it was supposed to do 71 72mph? My RPMs were also 7900 max