How to find the right Bike Headsets AI guide

Cane Creek: Wide standard coverage and clear SHIS labelling.
Chris King: Premium, very long-lived headsets.
Hope: Machined headsets in many fits.
FSA: Common OEM headsets and replacement bearings.
Wolf Tooth: Headsets in common standards.
Works Components: Angle-adjust headsets.

Written by an AI model from its trained knowledge.

What the AI looks for in Bike Headsets

SHIS sizing: Identify each cup by SHIS code, for example ZS44/28.6 for the upper and ZS56/40 for the lower: type, cup bore, then steerer size. This is the standardized way to match a headset to a frame and fork.
Headset type: The types are integrated (IS, bearing sits in the frame), zero stack (ZS, cup pressed in flush), external cup (EC) and threaded for quill bikes. The frame's head tube design dictates the type, and the types are not interchangeable.
Bearing contact angle: Integrated bearings come in 36x45 and 45x45 angles. The bearing must match the frame seat. A mismatched angle seats poorly and wears quickly.
Crown race: Match the fork crown race seat: 30.0 mm for 1-1/8 in and 39.8 mm for 1.5 in tapered. The crown race must press securely onto the fork.
Steerer type: Straight 1-1/8 in, tapered 1-1/8 to 1.5 in, or older 1 in. The upper and lower cups must suit the fork. The fork determines the bearing sizes.

Buying by description like 'tapered headset' without the SHIS codes for both cups.
Pressing cups without a proper headset press.
Replacing only the bearings with ones of the wrong contact angle.

Often, yes, on integrated headsets. Match the bearing outer diameter, inner diameter and contact angles exactly, or measure the old bearings.