Nine-speed drivetrains are still doing real work on training bikes, commuters, touring rigs, and older road builds that don't need the newer 11 or 12-speed treatment. The Shimano CS-HG400-9 in the 11-28T configuration is the go-to replacement cassette when one of those drivetrains wears out. It's an Alivio-tier part that Shimano officially positions for mountain and trekking use, but the 11-28T tooth range lands squarely in road territory—tight steps through the middle of the block, a usable 28-tooth bailout for climbs, and full compatibility with 9-speed road shifters like the ST-R3000 Sora and ST-R350.

The cog sequence runs 11-12-13-14-16-18-21-24-28, which means single-tooth jumps through the top five cogs where you spend most of your time on flat and rolling terrain. Once you get into the climbing gears, the steps widen out to give you the range without stretching the derailleur cage. If you're rebuilding an older Sora or Tiagra 9-speed setup, or keeping a beater bike alive, this ratio behaves like a road cassette even though the box says mountain.

Hyperglide tooth profiles and shift ramps handle the gear changes, and the whole thing installs onto any Shimano/SRAM 8, 9, or 10-speed freehub body with the included nickel-plated steel lockring. The nickel plating on the cogs shrugs off corrosion better than the raw steel finish on cheaper cassettes, which matters on commuters and rain bikes. Shimano also rates the HG400 for e-bike use, so if you're building or maintaining a pedal-assist bike with a 9-speed drivetrain, this is the cassette that meets their durability spec. Pair it with a 9-speed HG chain—CN-HG93, CN-HG53, or CN-HG54—and replace both at the same time for the cleanest shifting.