If I were to build up a lightweight XC bike from a Frame Up, and with the forks, headset you've already decided on, I'd spec the rest with the following. XTR Shifters (not dual Control), Hope Mini's or Hayes Mag Carbon discs. If you DO want the dual control, (not my preference) might as well get the XTR calipers, but not the hubs (you can run an XT 6 bolt rotor on the XTR). Wheels would consist of Chris King Hubs with X3.1 rims (as mentioned above). Front and rear derailleurs would be XTR (not rapid rise if possible), XT Cassette and and Sram PC-69 chain. Stem would be either a Race Face SYStem, (not Prodigy) or a Thomson. Seatpost would ONLY be a Thomson. Handlebars would be Easton Monkeylites (if Riser bars) or their carbon flat bar. Seats are such a personal thing, I can't recommend one. Grips, get some ODI lock-ons. I never thought that the ODI system was worth it, until I tried it. My grips don't move EVER! Tires, I'd look into INTENSE Tires. They have the SYSTEM 2 which are good all around tires. That or Maxxis tires. What else? Pedals? I'd go for my old reliable TIME A.T.A.C.'s over anything else.
L8R
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"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming, "WOW, What a Ride!" - unknown
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