I thought 1 1/8″ was all I needed to know? The shop that’s speccing a build for me said:

“Can you find out exactly what you need for your frame? All ours are 45/45 [degrees]. We’ve got a few 45/36 headsets in but they’re for older frames”

???

I can see that different contact angles might be more appropriate for different styles of riding, but how could the frame make any difference?

This is primarily a roadie shop btw.

Thanks!

Ask if they come with suitable crown races…

Once the British Empire had been forgotten all the standardised components were thrown out with the dishwater. Now we have at least 6 different headset standards – some of which have almost discernable differnece excpet that they won’t fit the other one.
You need to find out whether you have a Integrated/ Hiddenset/ Internal/ etc
Taken from the FSA guide to headsets:
What is meant by threaded, threadless, internal, and integrated headsets?
-Threaded headset cups press directly into the frame. The fork used for threaded headsets is threaded, and a large nut installed on the steerer tube is used to preload the bearings.
-Threadless headset cups also mount directly into the frame, but a star-nut or similar compression device installed in the fork is used to preload the bearings.
-Internal headsets are functionally similar to threadless headsets. The main difference is that internal cups press almost completely into the frame. These are often preferred for their low stack height and clean look.
-Integrated headsets are becoming more and more popular. With integrated headsets, a bearing (usually a sealed cartridge unit) s directly into the frame eliminating the need for cups. With integrated headsets, it is not necessary to press cups into your frame, but it is important that the headtube be professionally machined to the proper dimensions to ensure smooth operation.
What are the most widely accepted standards of integrated headsets?
While there are many standards out there, the three most widely accepted are the Cane Creek, the Campagnolo, and the TH standard. All three use angular contact bearings (ACB) which we find to be best suited to handle the loads to which a headset is subjected. Each bearing uses its own proprietary ACB standard and are of different dimensions. The bearings are not cross compatible. Cane Creek Standard integrated headsets use a 35°x45° angular contact bearing (blue seal), Campagnolo a 45°x45° ACB (yellow seal), and TH a 36°x36° bearing (red seal).

Thanks! I’ll have a read. The frame’s for external headsets, and I hadn’t considered that the guy in the might assuming that it might be otherwise.

is it an integrated headset?

IT woudl really matter as the bearing cups are machined into the headtube rather than usign separate cups.

so, generally, if the headset has separate cups that the bearings sit in there’s no problem as the cups will fit the bearings. If it’s an internal headset then it’s a good question and you’d need to talk to the frame manufacturer to find out what anlge they machine the cups to.

cheers wwaswas, I edited mine when I saw it had crossed with a useful answer.

no worries – you should be ok with any decent road headset (assuming it comes with a crown race).

So I might not get a crown race with an external headset? I’ve got so much to learn. Why the hell not? Do road forks come with an integrated, everlasting crown race?

It’s a bit of an ‘in’ joke – there’s 1100+ posts discussing it here;

http://www.singletrackworld.com/forum/topic/probably-a-stupid-headset-question

(headsets do come with a crown race, btw)

That’s the thing. I’ve seen the crown race thing on here pop up now and again, and commented on it myself a couple of times, but I’ve just found out something I thought was totally irrelevant was a perfectly reasonable thing to be asked.

I’m keen to learn, but that opens you up a bit! I’m half expecting someone to send me down to the stores for a long stand!