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01 YZ426 power mods got any ideas???

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I have a 01 yz426, I already have a full fmf exhaust system with powerbomb header, all jetted and added adjustable fuell mixture screw, the bike runs great. I also added renthal front and rear sprockets to lower the gearing a little bit for the tracks, what can I do to get a little more power??? I plan on making it a 450 when the top end craps out, but i think its going to be a while for that, because the bike runs like its brand new and starts on the first kick. I'm interested in a cam, port and pollish, valves, or anything to better help me keep up with these newer bikes, I want my bike to hit harder than my uncles 07 kx450 which is stock besides levers handlebars and suspension work, I have always had two strokes, someone please tell me what to do to make my 4-stroke way to fast for the average rider, I am never satisfied with the power output of any bike, i always want more, I was riding a rc51 when i was 18, so lemme know how to get the full potential out of this bike without spending a million dollars.....

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