If the total weight of your fully loaded backpack (w/o water and food) exceeds 10.5 kg (23 pounds) it is too heavy. It is recommended to make your backpack even lighter I'd say: 9 kg (20 pounds) is good.  

Banadana (1.2)
Sleeping Bag w/ compression sack (37)
Knife (0.8)
Green socks (3.3)
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Cup (2.9)
Golite Perspective pack (52)
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Poly socks (1)
Small blue stuff sack (0.5)
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Med. red stuff sack (1.1)
Zip pants (11.2)
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Nalgene (5.1)
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3 liter platypus (2.5)
Drinking tube and clip (2.4)
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