well well i have the infamous top end bog on my 580 efi. It will run great for about 40 miles then when u hit the gas it will go up to 7000 rpm and then just stay there. I go ahead and pull the plugs and they are BLACK.It runs so rich that the excess gas is spitting out of the exhaust and dripping down the cylinder. I change the plugs and it runs like a champ. Might light is bright and handwarmers work excellent so i dont think its the stator. What could it be ?