How big is a one inch headset?

Marty said:

I bought myself a nice new carbon fork and I thought getting a one inch headset would be easy, but
when I went to the local bike shop they don't seem to have that "old" size anymore. And the ones
they do have are either too tight or too loose. How big in millimetres is a one inch head stem?

Why the hell are there so many variations on one inch?

When I was a boy one inch was 25.4 mm. What size is it now?

The Headset entry of my Bicycle Glossary includes a detailed table with the various headset
sizes, see:

sheldonbrown.comgloss h.htmlOpen ↗

Sheldon "Numbers" Brown +---------------------------------------------+
| The nice thing about standards is that | there are so many of them to choose from. | --Andrew S.
| Tanenbaum |
+---------------------------------------------+ Harris Cyclery, West Newton, Massachusetts Phone
617-244-9772 FAX 617-244-1041 harriscyclery.comharriscyclery.comOpen ↗ Hard-to-find parts shipped Worldwide
captainbike.comcaptainbike.comOpen ↗ sheldonbrown.comsheldonbrown.comOpen ↗

Sheldon Brown wrote:

---8< ----- snipping

Quoted message said:

The Headset entry of my Bicycle Glossary includes a detailed table with the various headset
sizes, see:

sheldonbrown.comgloss h.htmlOpen ↗

Sheldon "Numbers" Brown +---------------------------------------------+
| The nice thing about standards is that | there are so many of them to choose from. | --Andrew
| S. Tanenbaum |
+---------------------------------------------+

Pls excuse my excursion OT, but can't resist commenting your mail footer.
Dr. Tanenbaum wrote the textbook used in a Comp Sci course I took in Australia back in 1977. But
that was back in the days when there didn't seem to be any standards at all, for *anything*.
Anyhow . . . cool to be reminded of some highlights from my dinosaur-age education ;-) /Robert

I used that book too - in 1996. Computer Networks, third edition, and I remember that quote. Funny I
work for Cisco Systems now - who'd a thunk it?

Kyle

Quoted message said:

Sheldon Brown wrote:

---8< ----- snipping

Quoted message said:

The Headset entry of my Bicycle Glossary includes a detailed table with the various headset
sizes, see:

sheldonbrown.comgloss h.htmlOpen ↗

Sheldon "Numbers" Brown +---------------------------------------------+
| The nice thing about standards is that | there are so many of them to choose from. | --Andrew
| S. Tanenbaum |
+---------------------------------------------+

Pls excuse my excursion OT, but can't resist commenting your mail footer.
Dr. Tanenbaum wrote the textbook used in a Comp Sci course I took in Australia back in 1977. But
that was back in the days when there didn't seem to be any standards at all, for *anything*.
Anyhow . . . cool to be reminded of some highlights from my dinosaur-age education ;-) /Robert

Sheldon Brown <[email hidden]> wrote in message
news:<[email hidden]>...

Quoted message said:

Marty said:

I bought myself a nice new carbon fork and I thought getting a one inch headset would be easy,
but when I went to the local bike shop they don't seem to have that "old" size anymore. And
the ones they do have are either too tight or too loose. How big in millimetres is a one inch
head stem?

Why the hell are there so many variations on one inch?

When I was a boy one inch was 25.4 mm. What size is it now?

The Headset entry of my Bicycle Glossary includes a detailed table with the various headset
sizes, see:

sheldonbrown.comgloss h.htmlOpen ↗

Sheldon "Numbers" Brown

When I tried out some threadless headsets, some appeared to be a press fit and others were loose,
about 0.4 mm oversize. Both are being sold as one inch. Why is there a difference and which one is
the real "one inch". (I found my vernier calipers and my stem is 26.4 mm or 1.04 inches)

Regards

Marty (Non-standard) Wallace

Quoted message said:

+---------------------------------------------+
| The nice thing about standards is that | there are so many of them to choose from. | --Andrew
| S. Tanenbaum |
+---------------------------------------------+ Harris Cyclery, West Newton, Massachusetts Phone
617-244-9772 FAX 617-244-1041 harriscyclery.comharriscyclery.comOpen ↗ Hard-to-find parts shipped Worldwide
captainbike.comcaptainbike.comOpen ↗ sheldonbrown.comsheldonbrown.comOpen ↗