Certified Refurbished & Pre-Owned Deals Outlet Deals Like New Tuttio ICT EbikeShimano Dura-Ace CS-R9100 Cassette

The Shimano Dura-Ace CS-R9100 Cassette sits at the top of Shimano's 11-speed road hierarchy — and the construction reflects that. The five largest cogs ride on dual multi-material carriers combining aluminum and carbon fiber, while the two smallest cogs are titanium for weight savings where it counts most. The remaining six cogs are steel, keeping durability where the drivetrain stress is highest.

Shimano also revised the tooth profile geometry on the R9100 to improve shift speed and smoothness across the range. The cassette is available in five ratios — including the wider 11-30 option for riders who want more range without stepping down a groupset tier, and two 12-tooth small-cog options for those who don't need an 11t regardless of the terrain. Each ratio has a verified weight: 175g (11-25), 193g (11-28), 211g (11-30), 189g (12-25), and 205g (12-28).

Shimano Dura-Ace CS-R9100 Cassette Specs at a Glance

• Speeds: 11-speed
• Available ratios: 11-25, 11-28, 11-30, 12-25, 12-28
• Cog materials: Titanium (smallest 2), steel (middle 6), aluminum/carbon carrier (largest 5)
• Weights: 175g / 193g / 211g / 189g / 205g (by ratio)
• Compatibility: Any 11-speed chain and rear derailleur; designed to pair with Shimano 11-speed road components