Well I'm looking at bout 45kg in total, 17kg for the bike including lights, rack and mudguards then 28kg kit including 3 full water bottles and the weight of the various bags and panniers. If I ignore the water and count the bags etc as part of the bike then I'm still looking at 21kg of luggage.
4.5kg - tent and sleeping stuff and that's a pretty darn light tent
2.5kg - electrics, smartphone with bracket, tablet, solar panel, MP3, headtorch and kindle, plus cables/chargers(though sharing these where possible)
1kg - cooking, stove, pots and pan, cutlery, herbs, salt and gas canister
1kg - wash kit including an Ortlieb folding bowl at 400g
1kg - folding chair, not essential but what the hell
3kg - tools and spare parts, half of this number is just a spare tire and spare tubes
7kg - clothes and shoes - though I suppose this includes what I'd be wearing at any given time and it includes waterproofs, hats, gloves etc
1kg - emergency rations and trail food
Some of the above allowances are quite generous and I know the chair isn't an essential but I struggle to see what can really be cut without compromising on comfort. I could also see the numbers climbing if I need to make use of the additional water bladder or drysack for extra food.