my carb only has one screw and that is the idle screw I got it started and rode it around the block and it went wide open again, I was able to kill it then kicked it again and it was fine rode about 30 feet and it went wide open again. there is a spring on top of my slide and I am thinking of replacing it too its a mikuni carb but all it says 00rp on it and I google it and get nothing in return