Have an 09 with 5 hours, it was sitting with gas in the carb for a while. When I'm riding it, the engine sputters if Im below 3/4 throttle. It cant keep a steady RPM without doing this, and the engine pops a lot when I let off the gas. I cleaned out the entire carb and all the jets yesterday, and replaced the spark plug, and it still has the same problem. I adjusted the fuel screw and I think that helped a little when I had it past 2 turns out. What could be causing this problem? the bike is basically brand new! I made sure the pilot jet was cleaned out, but should I just replace it? Also the jet baffle in the carb was loose after I put all jets back in, is that how its supposed to be?