Replacing a headset bearing isn't the kind of job you want to guess your way through — the wrong size, wrong stack height, or wrong angle and you're back to square one with the fork hanging out. The Ritchey WCS Drop In Upper Bearing is the direct replacement piece for Ritchey's WCS-level Drop In integrated headsets, sized to the IS42/28.6 standard for 1-1/8" steerers. If your frame uses a Ritchey Drop In integrated headset and the upper bearing is feeling notchy or rough, this is the part that gets it back to spinning smoothly without buying a complete headset.

The bearing is a 45/45 degree angular contact sealed cartridge, which is the standard interface Ritchey uses across the Drop In Integrated lineup. Angular contact geometry handles the combined radial and axial loads that headsets see — your weight pressing down, plus the side loading from steering inputs — better than a standard radial bearing. The cartridge is titanium coated for corrosion resistance, which matters in a part that sits right under your stem cap and sees every bit of sweat, rain, and bottle splash that runs down the steerer.

This is the upper assembly, so it ships with the top cap and the hardware needed to complete the install on a 1-1/8" steerer. Stack height is 8.3mm. Before ordering, check that your frame actually calls for the IS42/28.6 upper — Ritchey makes a separate Drop In lower assembly with the crown race, and the two aren't interchangeable. If your lower bearing is also due, you'll want to order that piece alongside this one.