12.2 kg sounds pretty light for a bike of that much travel, do you have a parts list?
Essentially:
Fork: RS Pike 150mm
Shock: Fox DPS EVOL (no piggy-back = almost 200 g lighter), enough for me
Cranks: E13 TRS Race Carbon (the XCX Race Mountain are even lighter, but said to be flexy)
Wheelset: homemade from Chinese carbon rims (30mm inner width) and
DT 240EXP clones, Sapim D-Light spokes = 1385 g
Cassette: E13 Helix-R
Rear derailleur: XTR
Pedals: composite
Saddle: Chinese carbon (so damn light and cheap, and perform well)