G´day Alan , You should´nt touch these air screws / pilot screws they are factory set & do not have any real influence over rich-lean adjustment . All adjustments should start with the slide needle height , factory set @ the centre of 5 positions . Shift down for leaner . These simple adjusts will usually cover a change of exhaust system . Change of cams , compression , CDI will require a few more tries . Your best bet is to get the bike on a dyno with full exhaust analysis . But keep an eye on those plugs & don´t burn any valves . Mark .