Ten-speed drivetrains aren't going anywhere. Plenty of road bikes on the road today are still running 10-speed, and if yours shifts cleanly and matches the riding you do, there's no real argument for jumping to 11 or 12-speed just because the industry moved on. The Shimano Ultegra CS-6700 10-Speed Cassette keeps that drivetrain running the way it was designed to, with the same Hyperglide tooth profiles, alloy carrier construction, and shift quality that made the 6700 series a workhorse across a decade of Ultegra builds.

Construction follows the pattern Shimano established at the Ultegra tier — the three largest cogs mount to an aluminum carrier that saves weight over an all-steel stack while keeping the sprockets rigid enough to shift crisply under load. The smaller cogs are individual nickel-plated steel pieces with machined cutouts that trim a few more grams without giving up tooth engagement. Hyperglide ramps and revised tooth profiles do the actual work of moving the chain between cogs, and they're the reason Shimano cassettes have felt so predictable for so long.

Four ratio options cover the range of road riding most people actually do. The 11-25T runs tight gaps for flat and rolling terrain where you want smooth cadence transitions. The 11-28T keeps the 11-tooth top gear for descents while adding a bailout cog for hillier days. The 12-25T is the classic mid-range spread for standard cranksets, and the 12-30T opens up serious climbing range for compact setups, loaded touring, or gravel-adjacent rides on a road bike. Heads up on that last one — the 12-30T needs a medium-cage rear derailleur to handle the extra capacity, so verify your derailleur before ordering.... Read More