Determining headset, head tube and steerer diameter measurements

[explodomac]

I've acquired a very large and possibly non standard old steel frame I'm going to use to build up an expedition bike. This will be my first bicycle build so I'll be learning along the way.

I'm hoping to build it from bits around the place, on the cheap, wherever possible (mates dead bikes, local 2nd hand bike shop parts pile etc) Due to the size of the head tube (213 mm length) I can't just throw on any fork so it looks like I'll be ordering one off the internet.

There are a few cheap forks with 250mm+ steerers around that are 1 1/8. My question is, using the internal head tube diameter (30mm) how can I determine what the diameter of the steerer should be? And consequently the headset?

I'm pretty new to this game and I appreciate any help I can get on this.

Cheers,

Jack

[RobAR]

Jack, see if http://www.sheldonbrown.com/cribsheet-headsets.html is the info that you're looking for. I bet it is!
By the way, browse that site for hours. Tons of info there!

Rob

[JohnnyCO]

You can use that inside diameter from the headtube and find a headset that fits. Threaded Headset:Make sure the new headset thread matches the new fork thread. Threadless: make sure the diameter of the headset and fork diameter are properly sized. Determine your fork length and headset stack height. Cut the fork if needed. Set the crown race on the fork. Careful not to damage the race. Threadless: set a star nut in the fork column. A little bit of math to do this but measure twice, cut once. Check out parktool.com for another resource

[JonB]

Quote:Threadless: set a star nut in the fork column. A little bit of math to do this but measure twice, cut once. Check out parktool.com for another resource

Or whack a Headlock, Hope Head Doctor, or similar in there. It's easier than a star nut and can be removed fairly easily as well. Downside is it's a bit more expensive. The Hope is a better one, but I have no idea if you can get Hope out in Australia

http://www.chainreactioncycles.com/Models.aspx?ModelID=911

http://www.chainreactioncycles.com/Models.aspx?ModelID=17766