The Shimano XTR CS-M9001 is the flagship 11-speed mountain bike cassette, engineered for riders who demand the lightest, most precise drivetrain on the trail. The 11-40T range delivers exceptional climbing capability without sacrificing high-speed efficiency, while Rhythm Step gearing keeps your cadence consistent through every shift.

Highlights

• Wide 11-40T gear range in an 11-speed package — ideal for technical climbs and fast descents
• Rhythm Step progression: each shift produces a consistent ~10 RPM cadence change for smooth, energy-efficient riding
• HG-X11 tooth profile with precision ramps and pickup points for fast, quiet 11-speed chain engagement
• Strategic multi-material construction: nickel-plated steel small cogs, titanium mid-range cogs, and an aluminium 40T large cog
• Carbon fibre spider arms connect the cog assembly for further weight reduction
• Mounts directly onto standard Shimano 8/9/10-speed MTB HG freehub — no adapter required

Materials & Construction

Shimano engineered the CS-M9001 with a targeted material strategy across its 11 cogs. The four smallest cogs — which absorb the highest chain loads during hard accelerations — are nickel-plated steel for long-term durability. The six middle cogs are titanium, balancing strength and weight where loads are moderate. The 40T climbing cog is anodised aluminium, keeping the overall weight at a featherlight 331 g. Carbon fibre spider arms tie the assembly together, reducing rotating mass without compromising rigidity.

Rhythm Step Gearing

Unlike cassettes with uneven steps that cause jarring cadence spikes, the CS-M9001 uses Shimano's Rhythm Step spacing across the full 11-13-15-17-19-21-24-27-31-35-40T progression. At a typical 80 RPM cadence, each shift results in approximately a 10 RPM change — keeping you in your power zone and reducing fatigue on long climbs or sustained efforts.

Compatibility & Fit

The CS-M9001 fits standard Shimano HG 8/9/10-speed MTB freehub bodies — no proprietary driver required. It is compatible with 1x, 2x, and 3x drivetrain configurations. For optimal shifting performance, pair with a Shimano HG-X11 or HG-901 11-speed chain. Note: if fitting to a road-style 11-speed freehub, a 10-speed conversion spacer is required. Compatible with XTR M9000 series derailleurs and other Shimano 11-speed MTB groupset components.