Shimano Ultegra CS-R8101 12-Speed Cassette | 11-34T | HG L2 Freehub
Shimano Ultegra CS-R8101 12-Speed Cassette | 11-34T
Wide-range gearing without sacrificing the fast, precise shifting Ultegra is known for.
The Shimano Ultegra CS-R8101 cassette is designed for riders who want exceptional shifting performance combined with lower climbing gears for mountainous terrain, endurance events, and gravel adventures. Compatible with both Di2 electronic and mechanical 12-speed Shimano road drivetrains, the CS-R8101 delivers smooth, reliable shifting across its entire gear range.
The 11-34T gear range offers additional climbing capability over the 11-30T cassette while maintaining closely spaced gears for efficient cadence during fast road riding. Whether you're tackling steep mountain passes, riding all-day fondos, or exploring mixed-surface roads, the 11-34T cassette provides the versatility needed for every ride.
Precision-engineered sprocket profiles produce fast, quiet shifts while reducing drivetrain wear. The cassette installs on Shimano's HG L2 road freehub, which is also compatible with most Shimano 11-speed HG road freehub bodies, making upgrades simple for many existing wheelsets.
Key Features
- Genuine Shimano Ultegra 12-speed cassette
- Compatible with both Di2 and mechanical shifting systems
- Wide-range 11-34T gearing for climbing and endurance riding
- Smooth, quiet Hyperglide shifting performance
- Lightweight, durable construction
- Compatible with Shimano 12-speed road drivetrains
- Excellent choice for road, gravel, endurance, and climbing-focused riders
Gear Range
- 11T
- 12T
- 13T
- 14T
- 15T
- 17T
- 19T
- 21T
- 24T
- 27T
- 30T
- 34T
Technical Specifications
- Brand: Shimano
- Series: Ultegra
- Model: CS-R8101
- Generation: Ultegra R8100
- Speeds: 12-Speed
- Gear Range: 11-34T
- Compatible Chain: Shimano HG 12-Speed
- Compatible Drivetrains: Shimano Di2 & Mechanical 12-Speed Road
- Freehub Compatibility: Shimano HG L2 / Shimano 11-Speed Road HG Freehub
- Cassette Type: Cassette
- Shimano Product Code: ICSR810112134
- UPC: 192790849881
Why You'll Love It
- Lower climbing gear without giving up smooth cadence transitions
- Ideal for mountainous routes, gran fondos, and endurance riding
- Fast, quiet, and dependable Shimano shifting
- Compatible with both electronic and mechanical Ultegra groupsets
- Outstanding durability for high-mileage cyclists
Compatibility
- Shimano Ultegra R8100 12-speed
- Shimano Dura-Ace R9200 12-speed
- Shimano 105 R7100 12-speed
- Shimano HG 12-speed chains
- Shimano HG L2 / 11-speed road HG freehub bodies
Before You Buy
- This cassette is designed for Shimano 12-speed road drivetrains.
- Compatible with both Di2 electronic and mechanical shifting systems.
- Fits Shimano HG L2 road freehub bodies and is backward compatible with most Shimano 11-speed HG road freehub bodies.
- Pair with a Shimano HG 12-speed chain for optimal shifting performance and drivetrain longevity.
The Shimano Ultegra CS-R8101 11-34T Cassette is the perfect upgrade for riders who want professional-level shifting with additional climbing capability. From steep mountain roads to long gravel adventures, it delivers the smooth performance and reliability that define Shimano Ultegra.