Bought two bikes, a 2009 and 2011. The 2009 is great, no issues whatsoever. The 2011 is a different story. It, unfortunately for me, has been modded. The floor board, stock seat, stock muffler and kick starter cover assembly has been removed. Guess the P.O. did this to gain some speed. I cleaned the carburetor in a ultrasonic cleaner making sure all the ports were clear. Pulled the fuel tank and dumped out the old fuel. Suprisingly, there didn't seem to be any rust or other junk present. Compression is about 120 psi and the spark plug is in good condition. After reassembly, I took the bike for a test ride and was surprised that it ran really well. Pulled a gradual incline keeping the speed around 30 mph. Continued on about a half mile when the bike stalled and would only run at idle. I'm thinking fuel pump as the output didn't appear to be quite the volume of the other bike. Just wondering if there is a strainer or something in the tank at the pickup.Letting the bike sit for about half an hour results in a quick start up and well running machine so I'm pretty sure it is a fuel issue. Any recommendations, advice would be greatly appreciated. Thanks!