Everyone is all happy and blessed out about Dura-Ace 9000 having 11-speeds and a new crankset. That's all well and good, but what we're really excited about is the brakes. Shimano 7900-series brakes were already some of the best in the biz, but the new Shimano Dura-Ace 9000 brake calipers take the stopping thing to a whole new level. Shimano redesigned the calipers so they now have a "true" dual-pivot design, so the mounting bolt no longer doubles as one of the pivots. This means that the brake is now positioned symmetrically over the wheel and applies equal cable pull to both arms, drastically reducing pivot friction and increasing stopping power by 10% over the 7900 brakes.
"True" dual pivot design makes the brakes more powerful and efficient
Mounting bolt is separated from brake body, so the brakes won't wobble when you pull the lever
Brake arms use a rolling cam so they pull independently and apply equal braking power on each arm
Arms use twin bearings to reduce pivot friction
Design allows brake pads to be positioned closer to the rim for more powerful braking performance and improved modulation