Would think it's a leaking injector!
Don: I would think that this is a leaking injector or such. When you kill your engine, you pull the engine kill pull. This is suppose to shut off the fuel supply. If the injector is leaking it may be dripping enough fuel to allow a build up in the cylinder. When you start your engine do you just move the throttle only slightly ahead? The only other thing is that you are maybe giving it slightly too much fuel on start-up. Just a couple of ideas.
