I have an 04 sportsman 600 twin. This season it started to quit when it warmed up. It was dumping fuel into the air box. I did a carb rebuild and found the needle and seat were shot. Runs like new again….until it gets hot and it still quits except no more fuel leaking. This happens after about 15 minutes, idling or driving. The fan kicks on and when it goes off the bike quits and won’t start again til it cools completely. When it quits the coil is still providing good blue spark at the plugs. The plugs are a little carbon fouled too. Anyone have any suggestions at all? The dealer told me today the valves may be too tight but I don’t believe that would cause my symptoms that just started after plowing with it all winter. After winter I changed all fluids except antifreeze. I do have an aftermarket fan that was much cheaper than the $300 one from the dealer. I’m at a loss on this and it’s killing me with riding season upon us.