Headsets
Used road headsets let the fork rotate in the head tube for steering, with modern bikes using integrated or semi-integrated designs and cartridge bearings pressed into the frame. Chris King, Cane Creek and Hope make premium sealed-bearing headsets that last years, while budget units from FSA, Ritchey and Neco work perfectly well with bearings that wear faster. Getting the right headset is a matter of matching dimensions precisely.
Integrated, semi-integrated or external?
Integrated (IS) headsets have bearings sitting directly in the head tube — the most common modern standard, with no pressed cups and the bearings dropping into machined races in the frame. Semi-integrated (ZS) headsets use bearing cups pressed into the head tube with the bearings sitting inside the tube. External (EC) headsets have cups pressing onto the outside of the head tube, the traditional standard on older bikes. Each type has a specific designation — IS42, ZS44, EC34 and so on — defining the bore diameter. Your frame determines which type you need, and there's no converting between them.
How do I match the dimensions?
Headset standards are defined by the head tube diameter, with 1-1/8" upper and 1-1/2" lower for tapered setups. Check the crown race — the lower bearing seat on the fork — fits your fork steerer diameter, as this is easy to overlook when buying a headset and fork from different sources. Take the bore designation and steerer diameter as a pair, and confirm both before money changes hands.
Are Chris King and Cane Creek worth the money?
Chris King headsets use their own precision bearings with user-replaceable seals and last 10+ years with periodic service. Cane Creek 110 uses a similar approach with Norglide bearing technology, and Hope headsets use high-quality sealed cartridge bearings. Budget headsets (FSA Orbit, Neco) use standard cartridge bearings that work but may develop roughness after 1-2 years in wet UK conditions — the same weather that eats through bar tape and the rest of your contact points.
Can I just replace the bearings?
Headset bearings are cheap to replace; the cups and races are the valuable parts. Aftermarket replacement bearings from Enduro Bearings or Acros fit most headsets, and Chris King bearing replacement kits are readily available. Ceramic bearings exist but offer negligible real-world benefit in a headset, so put the money into the cups instead and browse the component listings for a quality body rather than a complete cheap unit.
What should I check buying used?
Rotate the steerer tube — the headset should turn smoothly with no notching, which indicates brinelled bearings where the balls have dented the races. Check for play by holding the front brake and rocking the bike forward and back; any knocking means the headset is loose or worn. Chris King headsets are excellent used buys because the bodies last decades. Confirm the crown race matches your fork steerer diameter before you commit.