Are we talking about the older Sora available with $500 bikes like the OP is referring to? Then its definitely 1+ pounds heavier than 5800. I wrenched in an LBS for a bit and handled quite a bit of the Sora vs 5800 stuff. The hollow-tech crankset is a good 200+ grams lighter than the Sora crankset. The Sora BB is also 250 grams compared to < 80 grams for the BB86 BB.
Weight aside, the brakes on the 5800 groupset are tremendous and a great improvement as is the shifting, in particular the FD.
Originally Posted by
Karman321
trust me its heavier, every gram adds up
Originally Posted by
Lazyass
I would be surprised if Sora weighed even a half pound more and if anyone could tell any difference between the two except for the one cog. And most people wouldn't even notice that. Do you actually know the weight of each group?