My wife's klx140 will not start. I can hear the starter motor and the engine does WANT to start but it just won't. I washed it, and after I washed it, I went to start it to let the water evaporate off the engine. I usually use the throttle when it's cold to start it but when I let go of the throttle, it turned off. (That's normal when it's cold) but this time, it didn't want to start up anymore after that. The battery is fine and so is the starter. The spark plug looks okay too. I checked the air filter, and everything seemed okay. Does anyone have any idea what it could be? Carb, fuel petcock, fuel line, valves? What could it be? Any help will be greatly appreciated! Thanks!