new fd/cranks - new R9100 chainrings/cranks spacing (also new 105 fd will be released for this spacing FD-5801) new pedals - same weight/materials as old dura-ace (PD-9000) new cassettes - all combos (11-30T), plus one special 11sp cassette 11-34 compatible with 10sp freehub (CS-HG800) new rear derailleur - SS same as R9100 (capacity 35T, max 30T), GS version (capacity 39T max 34T) - different to 6870