This set of pulley wheels features SHIMANO's advanced technologies

Result: a quieter chain with faster

from intense workouts to casual outings

Crafted with precision

4 x spacers

shimano ultegra cassette cs r8101 12 index51 This set of pulley wheelsThe uninterrupted shifting experience of the ULTEGRA R8100 12 speed cassette range lets you climb, sprint, or cruise without stopping to think about your next gear change. Larger driving cogs maximize drivetrain efficiency and create compatibility with both Shimano 11 and 12 speed FREEHUB bodies. HYPERGLIDE+ cassettes revolutionized off road shifting with its seamless shifts both up and down the gear range.