The uninterrupted shifting experience of the ULTEGRA R8101 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.

Take your road bike performance to the next level with the Shimano Ultegra CS-R8100 12 Speed Cassette. Designed for Shimano’s latest generation 12-speed road drivetrains, this cassette delivers fast, precise and reliable shifting across every ride — from high-speed bunch racing to long alpine climbs.

Featuring Shimano’s advanced HYPERGLIDE+ technology, the Ultegra CS-R8100 cassette provides smoother gear transitions, improved chain engagement and confident shifting under load. Whether you’re sprinting, climbing or pushing through changing terrain, every shift is engineered for maximum efficiency. 

Available in 11-30T and 11-34T gearing options, the CS-R8100 gives riders the choice between a close-ratio setup for fast road riding or a wider range cassette for tackling steeper climbs and endurance riding. 

Built with Shimano’s renowned durability and race-proven performance, the Ultegra 12-speed cassette is the perfect upgrade for riders running Shimano Ultegra Di2, Dura-Ace R9200 or compatible 12-speed road drivetrains.

Features

• Shimano Ultegra R8100 series 12-speed cassette
• HYPERGLIDE+ technology for faster, smoother shifting
• Optimised gear progression for road cycling performance
• Available in 11-30T and 11-34T options
• Compatible with Shimano 12-speed road drivetrains
• Ideal for racing, endurance riding and performance upgrades
• Lightweight construction with Shimano durability

Specifications

Brand: Shimano
Model: CS-R8100
Series: Ultegra R8100
Speeds: 12-speed
Gearing Options: 11-30T / 11-34T
Cassette Type: HYPERGLIDE+
Compatible Chain: Shimano HG 12-speed
Average Weight: Approx. 291g (11-30T) / 345g (11-34T) 

Specifications
Refined 12 step gear combination provides peak efficiency and accelerating performance for every racing situation
Faster, smoother shifts under maximum pedaling force
Compatible with new 12-speed and road 11-speed FREEHUB body

Mfr Claimed Weight
291g (11-30t)
345g (11-34t)