High-Quality, Consistent Rolling Efficiency: The hubs feature high-quality contact seals and the iconic Shimano Cup & Cone bearing system,  which provides smooth and consistent rolling efficiency and top-level performance output. The rear wheel features Shimano's OPTBAL 2:1 spoke lacing, which means the drive side has twice as many spokes as the non-drive side. This spoke lacing pattern increases stiffness and stability, while lowering flex to the point where it is non-existent; it is a noticeable increase in power-transfer and rider-confidence when racing at your true potential.