The Shimano S-PHYRE RC910 road cycling shoe carries a carbon hollow core sole that sits closer to the pedal axle than any Shimano road shoe before it, putting more of each pedal stroke directly into forward motion. This build uses the DYNALAST 2. 0 narrow last, which still widens the forefoot and softens toe spring relative to the outgoing platform while wrapping closer around a slimmer foot. Dual BOA Li2F dials with textile laces close down evenly across the foot, and a reinforced carbon heel structure keeps the foot from twisting loose during a hard sprint. What Our Gearhead(R) Experts Are Saying:"I felt the lower stack height the first time I stood up on a climb, my foot sits right on the pedal instead of stacked above it, and that translates straight into how much power actually gets through."