Shimano R8170-C60 ULTEGRA 60mm Clincher CLULTEGRA 8100: Join the Pursuit of Next Level Speed Shimanos new ULTEGRA line up dives into what is ready behind the science of speed with real world applications. Following in the footsteps of the DURA ACE design philosophy, and using many of the same product designs, including the new addition of the 12 speed rear, ULTEGRA is joining the pursuit of next level speed. Wheel System: Aerodynamics, Rigidity, & Lightweight The last pillar in ULTEGRAs