Help, my 2007 rxp has 36 hours and ran great last summer. After sitting up for the winter I changed the oil, filter, and plugs and took it out for a run. It appears to have a very slow start out of the hole with limited top end. Last summer it would run 65 mph ++. In an attempt to fix it I replaced the fuel filter and did seem to fix it. Run great at idle and all rpms. Max RPM currently are 6500 -6800. What should I check next? Dealer says its the supercharger! I don't have any fault codes.