I just purchased one last Sunday. It wouldn´t start because of dead battery and old gasoline. Draining the carbs and tank, then adding new gas (and a new battery) produced a bike that would run on choke only. Used carb cleaner on the floats (which were stuck open) and the jets, still only ran with choke, opening the throttle killed it. Took apart carbs again, left float stuck again, cleaned that. Sprayed Gumout into every hole I found. Noticed the CV gates were stuck, so soaked them in Gumout and pried them loose. Bike started and reved up with application of the throttle. Drove it about 1/4 mile in the neighborhood before it quit. Now runs only with choke again. Plan to tear the carb completely apart this weekend and soak thoroughly in Gumout, maybe overnight. Carb is more complicated than I am used to working on (R5 & RT180) but I think I am on the right track.