So, to start, the weight of the bike with the 30 speed SLX gears was
29.63 lbs
Then I removed;
XT rear hub, XT skewer, 32 x 290mm spokes and stainless nipples, 11-34 10 speed cassette, 10 speed chain, SLX rear mech, SLX front mech, standard SLX chainrings, left and right SLX 10 speed shifters and cables and 2 zip ties.
Added were;
Alfine 8 speed hub with 20T Alfine Sprocket and fitting kit, 32 x 285mm spokes and stainless nipples, Alfine 8 speed trigger shifter and cable, BETD Goldtec 32T chainring, 4 x 5mm spacers (to get chain line and utilise standard chainring bolts) and SRAM PC7X Chain.
Weight of bike with Alfine was
29.68 lbs
However, that was all done at my mates (weighed with the gear cable wrapped round the handle bars), next day at home I came to set the gears up and found the gear cable was way too long, shortened it by 480mm and weighed in (at the post office) what I removed at 19 grams which converts to 0.04 lbs and brings the total bike weight down to
29.64 lbs
So to summarise, my bike with 8 speed Alfine is 0.01 lbs (0.008 lbs or 0.13 oz or 3.68 grams to be exact) heavier than the when it was equipped with 30 speed SLX which I think you’ll agree is diddly squat.