Bicycles Stack Exchange is a question and answer site for people who build and repair bicycles, people who train cycling, or commute on bicycles. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I want to buy a threaded headset for an old road frame that takes 1 inch threaded steerer tube / headsets. I see headsets for sale online that are labeled as "1 inch threaded BMX headset". Is there any compatibility issue with trying to install it on a road bike? What about non-BMX-labeled headsets being installed on BMX frames?

I figure I can get a headset a little bit cheaper if I could use one that is labeled as "BMX".

share|improve this question
up vote 1 down vote accepted

No, they're not interchangeable. BMX 1" threaded headsets have an outer cup diameter of 32.7mm - they wouldn't fit in a standard road frame. Standard (ISO) threaded headsets have an outer cup diameter of 30.2mm - they'd fit loosely in a BMX frame.

Sheldon Brown's Bicycle Headset Dimension Cribsheet is a useful reference for headset interchangeability.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.