I am going to take off the steel fork on my GT Force road bike (mostly because Nashbar has the threaded forks on sale) and I was wondering where I measure the steerer length from? Is there a way to measure without removing the fork that is on there?

I don't know if the bike is C&V, as it's only a 1999 (really, how many double triangle GT frames do you see out there?), but you guys are my buddies and I respect your knowledge.

Yes, the steerer is measured from the "land" that the bearing race sits on just above the fork crown. The bearing race will be plated either chrome or black and will be the upper-most part of the fork that is below the headtube of the bike. (the headtube will include the lower cup at this point) The other end of the steerer is just below the headset lock nut (about1/8" or so under the nut end). Since the head tube bulges out a bit and makes it difficult to get an accurate measurement, I would bend a 12" piece of coat hanger wire into a "C" shape to use as a caliper of sorts to span the distance.

I will snap a pic a bit later and mark it up for a clearer description if no one else has.

Actually - is there a way to know what length steerer a 60cm frame needs? That'd be easier.

You will probably be able to get by with the 220mm, but you should measure to be sure. Not all 60cm bikes have the same size headtube. I would just pull the old fork out and measure it, it is worth the effort in my opinion.

-Jake

...or just measure the headtube and add 40mm for a threaded headset or at least 85 for threadless.

SP
Bend, OR

That works pretty well for most. And yes, frame size does not relate mfg, to mfg. for a given frame size. Bottom bracket drop and top tube length, and to a small amount head tube angle all make a difference.

I measured between the cups on the headset and came up with 6 1/8 inches - which puts me at 155+ mm. So I would think the 200 or 220. Amirite? Should I do the 220 to be safe or should I do the 200. At 59.95 it's worth a try. I'm sure there is a coupon in my house or email somewhere.

Personally I think you should have followed FTWelders advice. do you intend to reuse your current headset? if not what is the stack height of you new headset?

if your headtube measures 155mm, then you add (as Bobbycorno points out) 40mm for a nominal headset stack/height that gives you 195mm for a steerer.

if your looking at the fork at the top of the page (at Nashbar) it shows the fork to have 50mm of threads. the 200 may work depending on your headset stack

if yur bike is setup (like many of mine) with the stem at the max height mark you may consider the 220 to get a bit more height but then you might be at the mercy of the LBS to cut some threads for you.

OH are you installing this yourself?

Headtube legnth + headset stack height should get you close. If it ends up just a bit too long, it's easy enough to cut it down a bit to accomodate what the particular headset brand requires in terms of how much treaded tube it could accomodate under its top lock nut, as they are all a little bit different in that area.

Chombi