I have a gx 1000 concourse 2001 bike ride runs fine around town just can't get up to speed on the highway just won't go past 4000 RPM or 80 miles an hour I have an aftermarket carburetor on it that you tune with sponges they're different sizes and prevents Hydro lock so maybe I'm running to leader to Rich or maybe I need a valve adjustment I don't know the bike is new to me so I'm not sure how fast I should be going around town so maybe the whole thing is not running right