Shimano Ultegra BR-6700 Brake

Servo-Wave. This unique Shimano feature has now made its way into road brakes and can be found when you mate these Ultegra BR-6700 brake calipers with the ST-6700 brake levers. Same basic design at the 7900 Dura-Ace, just a little heavier and a lot cheaper. The Servo-Wave is what has improved modulation and power. Servo-Wave in the brakes also means you've got to use these calipers with 6700 or 7900 levers or they are not going to work, at least according to Shimano. Servo-Wave also means they've redesigned the arms. In addition to curves that work better with the increased cable pull at the lever, they've redesigned the arm that houses the cable stop. This arm has been moved and the stop angle changed for better cable routing, which has the effect of reducing cable friction. The arm position also reduces the likelihood of the brake slamming against your downtube on those rare occasions when your front wheel flips hard to the right. Beyond Servo-Wave, they've also improved their braking compound. The new compound improves braking power by 20% in the dry and 100% in the wet. The spring tension in the calipers can also be adjusted to get a feel that's more in tune with your braking style. Brake shoe toe-in is adjustable.