The 2017 Shimano Dura Ace 9100 Groupset is a top-of-the-line mechanical road group. Refinements for 2017 are many: one of the more notable is the appearance of a power meter. Visibly almost identical to the four-armed Hollowtech crankset, there is only a slight bulgein one of the interstices, where the brain and communications center reside. The sensors, one in each arm, are invisible.
The dual-control levers have a new look, and a new feel. The hoods are textured, another first. The front derailleur has some slight changes, shifting a bit more smoothly than the 9000; the rear is a bit more dramatic. Shimano's off-road groups have brought the derailleur body closer in for protection, a change called Shadow; this is now incorporated into the Dura Ace rear derailleur. In case of a spill, the skewer will be the first thing to hit the road.
Rim braking is now a bit more versatile. The redesigned calipers can manage 28mm tires; the dual-pivot includes a brace, offering measurably increased stiffness. The quick release now aligns with the brake when closed.
An excellent road group.
