Howdy, I've got an '81 special ii that I've been doing some work on. Motor specs are stock motor, BS34s, 2 into one exhaust, free-flowing muffler, pod filters, and Canadian needle set. right now i have 45 pilot, 145 main, needles raised to fourth notch. I go to run a full throttle test, and it gets to about 4,500-5,500 and hits a flat spot in the power band, and can't get past that, even with it held wide open. I've tried new plugs, richened the needle from third notch to fourth and see very little difference. Adjusted float level to spec and still no big difference. Its running pretty lean, after checking plugs, porcelain's almost stark white. Do I have a clogged fuel filter or a crappy fuel line or what? Feel like richening my needle won't help too much and its running really lean for a decent size main. I'm in western Missouri if that helps much on altitude or air pressure. Please help!