Shimano Deore XT 10 Speed Cassette

Description

Shimano Deore XT CS-M771-10 Mountain Bike Cassette, 10 Speed, 11-32t, DynaSys HG

Has been inspected, ultrasonic cleaned, and lubed. Ready to be used.

Inventory number: 09146

The Shimano Deore XT CS-M771-10 cassette is a significant component in the mountain biking world, representing a pivotal era and technology shift for Shimano.

Industry Information

• XT: The Performance Standard: The Deore XT series is Shimano’s second-tier mountain bike groupset. Much like Ultegra on the road side, XT is known for providing nearly all the performance and reliability of the top-tier XTR components but at a much more accessible price point. The M771-10 cassette was a key part of the XT M770 groupset, which was released in the late 2000s.
• The Dyna-Sys Revolution: The CS-M771-10 was one of the first components to feature Shimano’s Dyna-Sys technology. Dyna-Sys was Shimano’s answer to the rising demand for simpler, more efficient mountain bike drivetrains. It was a complete redesign of the drivetrain concept, focusing on:
  • 10-Speed: It introduced a 10-speed cassette to the mountain bike world, which was a significant increase from the previous 9-speed standard.
  • Wide-Range Gearing: The 11-32t range was revolutionary at the time. This wide range allowed riders to tackle a greater variety of terrain, from high-speed descents to steep climbs, without the need for a front triple chainring. It made 2×10 setups much more viable.
  • Rhythm Step Gearing: Dyna-Sys was about more than just an extra gear. The cogs were spaced to provide closer gear ratios, allowing riders to maintain a consistent cadence and more efficient power transfer. This was a major selling point for serious mountain bikers.
• High-Quality Construction: The M771-10 cassette featured an alloy spider or carrier to which the largest cogs were mounted. This design provided a couple of key benefits:
  • Reduced Weight: By using an aluminum spider for the largest, heaviest cogs, Shimano significantly reduced the overall weight of the cassette.
  • Freehub Body Protection: The larger base of the spider prevented the individual steel cogs from gouging into the splines of aluminum freehub bodies, which was a common problem with older cassettes.
• Hyperglide (HG): The cassette utilizes Shimano’s standard Hyperglide tooth profiles, which are computer-designed with shift ramps and gates for smooth, fast, and precise shifting, even under load.

Compatibility

Compatibility for the CS-M771-10 cassette is crucial, as it is a highly specific component of a broader system.

• Drivetrain Speeds: The cassette is designed to be used exclusively with a 10-speed mountain bike drivetrain. It requires a 10-speed chain, and the shifting is only compatible with Shimano Dyna-Sys 10-speed shifters and rear derailleurs.
• Freehub Body: The cassette is compatible with a standard Shimano/SRAM HG (Hyperglide) freehub body. This is a major advantage as it will fit on a vast majority of mountain bike wheels from the past several decades. It does not require the newer, proprietary freehub body designs like SRAM’s XD or Shimano’s Micro Spline.
• Derailleur Compatibility: For the 11-36t range to work correctly, the rear derailleur must have enough chain wrap capacity. It is specifically designed to work with Dyna-Sys 10-speed rear derailleurs (like the XT M770/M780 series or XTR M980 series), which have a longer cage and are optimized for the wider gear range.
• Chain: The cassette is designed for a Shimano HG-X 10-speed chain. This chain has a specific asymmetrical plate shape that improves shifting performance with the Dyna-Sys system. While other 10-speed chains may work, a Shimano HG-X chain is recommended for optimal performance