Some of the biggest changes in the new 9100 group can be found in the front derailleur. The Shimano Dura-Ace FD-9100 changer, both the F (braze-on) and the B (clamp-style), make front shifting easier and more accurate. Whether it's better aerodynamics or just better aesthetics, Shimano did a good job making the derailleur linkage ore compact. That it is more compact is a plus, but is part of several improved features. A wider linkage setup, which makes the shifter stronger and stiffer, and loses less energy to torsional flex. The cable pull arm has been redesigned to be shorter and allow a more direct line from the frame exit point to the derailleur. The won't kink and the efficiency is improved. Finally, there's a cable-tension adjuster on the derailleur itself, so you don't need to install an inline adjuster on your cable housing. In addition to the derailleur movement, the cage itself has been redesigned to better accommodate the wider sixteen-tooth jumps that are increasingly common these days-think 50/34 and 52/36. Finally, the design, while backwards compatible with 9000-era shifters and cranks, also works better with shorter, wider chainstays, which are typical on disc-brake road bikes. Weight for the Shimano Dura-Ace FD-R9100 is 69g for the braze-on model. There are both braze-on and clamp versions available.