I have not ridden my bike for a while. When I went to start it I pulled out the choke and the bike started fine. Once it had warmed up sufficiently I pushed the choke in and the bike dies. I choked it again and it started, I can push the choke in part way and try and throttle, but the bike sputters and still dies when I push the choke in all the way. I pulled off the tank and drained all the gas, but still have the same problem. Any suggestions?