The Ritchey WCS Drop-In Upper Bearing IS42/28.6 is a premium headset component engineered for bikes that use an internal 42 mm headtube and a 28.6 mm fork steer tube. Part of Ritchey’s top-tier WCS (World Championship Series) lineup, this bearing delivers smooth, low-friction rotation and exceptional durability — ideal for riders who want dependable performance in road, gravel, or mountain applications where precise steering feel matters.

This drop-in upper bearing features high-quality, sealed cartridge bearings that resist dirt, water, and contaminants to extend service life and reduce maintenance. The robust construction and precision tolerances ensure consistent engagement with compatible headset cups, promoting confident handling and reliable responsiveness. Designed for standard IS42/28.6 headset interfaces, it installs easily with common press tools and pairs seamlessly with matching lower bearings and cups.

Whether you’re refreshing worn headset parts or building a new bike with high-performance components, the Ritchey WCS Drop-In Upper Bearing IS42/28.6 stands out for its blend of smooth operation, long service life, and compatibility with modern frame standards. It’s a go-to choice for cyclists and mechanics who value refined steering performance without unnecessary complexity.