Shimano WH-R8170-C60 Ultegra Disc Carbon Clincher 11/12spd Rear Wheel

Designed for the highest speed environments and modern tire widths, the ULTEGRA C60 rear wheel shares its all-carbon rim profile with DURA-ACE
but employs a hub that is compatible with both 11 and 12-speed cassettes.

For situations where aerodynamics is the priority, the new ULTEGRA R8170 C60 rear wheel features an all-carbon, 21 mm internal, tubeless compatible rim and a super-fast cup and cone bearing hub that is compatible with both 11 and 12-speed cassettes.

Key Features:

• 60 mm height full carbon rim
• Internal rim width: 21 mm
• Shared rim profile with R9200 DURA-ACE wheels
• Improved aerodynamics

Center Lock
The CENTER LOCK system makes an easy rotor installation possible with a spline mount and a lock ring. The lock ring mounting system reduces the total working hours by shortening the amount of time of both installation and de-installation. In addition, the secure fixing by the spline mount enhances precision and rigidity while improving braking efficiency.

D2
Aerodynamic performance is affected by wind direction. To create the D2 rim, SHIMANO engineers considered both frontal and crosswinds, aiming to achieve optimal performance in real-world riding conditions. Extensive prototype testing, in the wind tunnel and on the road, proved that a wide rim shape with a deep tire bed performs best across a wide range of conditions. At yaw angles ranging from 0 to 15 degrees, the SHIMANO D2 rim profile reduces air drag better than other aero shape rims. This rim design also boosts lateral wheel stiffness and offers improved vertical compliance for increased control, comfort and durability on the road.

Optbal
The OPTBAL rear wheel spoke system features 21 spokes—14 on the drive side and 7 on the non-drive side. Cassette spacing in today’s wheels produces unbalanced tension in traditional 1:1 spoke systems. This unbalance is intensified with the 11-speed cassette, producing nearly double the tension on the drive side spokes. Generally, high and low tension spokes have respectively tendency toward breaking down and coming loose spoke nipples. Unbalanced tension affects durability and strength. The OPTBAL design rebalances spoke tension, enhancing wheel rigidity and strength for a more durable wheel.

E-Thru
The tool-less type thru-axle skewer system optimizes rigidity and weight balance and enables easy operation with a reliable internal cam mechanism. The 15 mm thru-axle system is 15% stiffer torsionally and 25% stiffer in transverse shear than a traditional 9 mm quick release front axle system. High rigidity is secured while keeping the optimum weight balance. The E-THRU axle hub system minimizes the distortion of suspension while maintaining lightweight for riding around sharp corners at high speed.

Science of speed
Wheel performance is determined by three factors: aerodynamics, rigidity, and weight. The new Shimano road wheel collection optimizes the balance of those characteristics based on specific applications like climbing, all-around performance, or high-speed scenarios. Wheels unlike any other. One pedal stroke and you’re off.