fork steerer diametres

[uMP2k]

Just wondering if somebody can clear this up for me.

As my current bike is a much loved mid-80 vintage, the whole world of carbon forks and threadless headsets is a bit strange to me! What I am trying ot work out is whether the description 1 inch (25.4mm) or 1 1/8 inch (28.6mm) refers to the actual steerer or to the headtube it is designed to fit into. With the new types of fork/headset/stem combinations how much space is there between the steerer and the actual inside surface of the head tube - I presume it should be a fairly snug fit?

Any comments welcome!

[mikesbytes]

Can you post a picture of the head of your frame

[uMP2k]

Can you post a picture of the head of your frame

Will do when I get home from work! The frame in question is a 2004 Apollo RD Z1000 that I am building up for a friend and they are looking at putting carbon forks on it.

[Mulger bill]

AFAIK the sizing is the actual diameter of the steerer tube.

Bruce, my old Shogun MTB got a conversion from a 1 inch rigid fork to a 1 1/8 suspension fork with a headset swap.

Not sure if this applies to roadies too, I don't keep any references at work to check.

Hope this helps.


Shaun

[LuckyPierre]

The diameter refers to the actual steerer, but I think that the issue of fit is pretty complicated - almost variable from frame to frame. Things to consider include head tube diameter, whether the frame was designed for an integrated headset or not ......
But - I've sourced (fleaBay) a 1" threaded carbon fork as an experiment. If it works out OK, I'm thinking of getting a more serious one for a project. There are 1" carbon forks available, ie. http://cgi.ebay.com.au/Reynolds-Ouzo-Pro-Carbon-Fork-1-x-43mm-rake-NIB-NR_W0QQitemZ250078553078QQihZ015QQcategoryZ56196QQrdZ1QQcmdZViewItem.
You might get a 1 1/8" fork to fit in a frame that once had a 1" fork, but it would pretty much be pot luck.

[uMP2k]

Here is are two photos of the headtube in question:



Any ideas what sort of headset/fork I need?

[Mulger bill]

It looks like you might need a 1 inch steerer, with a standard, (non integrated) headset. Bit hard to be sure, your LBS will definitely be able to help, you'll need them to fit the headset anyway, I wouldn't recommend the "lump of wood and a hammer" installation.

[Mulger bill]

Sorry, forgot Can you get a threadless headset for a 1 inch steerer? (showing total ignorance of roadie tech again )

[uMP2k]

It looks like you might need a 1 inch steerer, with a standard, (non integrated) headset. Bit hard to be sure, your LBS will definitely be able to help, you'll need them to fit the headset anyway, I wouldn't recommend the "lump of wood and a hammer" installation.

That is pretty much what I thought! I will take the frame down to the LBS and find out for sure.

BTW - good to get a response so late in the night for somebody in the East!

[Mulger bill]

No worries mate, it's called Arvo shift.

Shaun