Long-time bicycle chain brand KMC has just introduced their new React cassettes in 10-speed and 11-speed versions. First spotted at Eurobike 2023, they’re designed for wide-range 1x and 2x applications, with tooth counts good for road, gravel, and mountain bikes.
At just $65, they’re affordable replacement, option for your trainer, or way to try a different tooth count on the cheap. Perfect for upgrading your kids’ bikes, too. And from the looks of it, you won’t be giving up shift quality to save some coin.
The cogs have dual shifting ramps called Flow Control, smoothing upshift and downshifts. These ramped tooth profiles & thicknesses use varied shapes to guide the chain from cog to cog.
Both KMC REACT versions have two gear range options:
- 10-speed: 11-36T, 11-42T
- 11-speed: 11-42T, 11-50T
They’re optimized for KMC chains, but are compatible with other 10- and 11-speed chains. They fit Shimano HG freehub bodies. Fitting it to a bike built around a smaller cassette? They recommend adding the Wolf Tooth Components Goatlink to increase your derailleur’s capacity for larger cogs.