There is a way that makes this possible but it depends on the length of steerer already in the fork and how much longer it needs to be. What can be done is to cut off the offending shorty and braze a new section on top of it using an internal sleeve to hold the 2 together. A steerer is a single butted tube where the lower part is thicker and then it tapers to where it is thinner. The cut off needs to be long enough above where the taper stops so the sleeve is long enough so it can have enough support in the old steerer. The sleeve will need to stick an equal distance into the new steerer. Now this sleeve needs to be down far enough from the top so it doesn't interfere with the insertion of the stem. If those conditions can be met, then part of the old steerer can be cut off and a new longer section of steerer brazed back on. I've done this on frames where the threads were badly damaged and I didn't want to mess up the historical paint of the fork.
Doug Fattic Niles, Michigan USA (which, by the way for those that don't live in the States, is pronounced more like "Mishigan". It is a soft rather than hard sound after the Mi. I've often been amused when traveling abroad - particularly in the UK - to have people correct my pronunciation of my home state. I suppose because I'm not speaking the King's English it is natural to assume I'm butchering this pronunciation as well.
On 10/20/07 5:04 PM, "email@example.com"
> Date: Sat, 20 Oct 2007 13:10:54 -0700 (PDT)
> From: bruce thomson <firstname.lastname@example.org>
> To: Classicrendezvous@bikelist.org
> Subject: [CR]Lengthening a fork steerer tube, how to?
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> Fellow travelers, I have been looking for a correct replacement for one of my
> bikes and often find the correct make of fork, but the wrong length of
> steering tube. Is there any experience among you to offer any direction to
> marry a longer threaded portion on to a shorter steering tube and produce a
> safe fork?
> Bruce Thomson Spokane WA 99204
> (509) 747 4314