Extending a cut steerer tube on fork

[Tarwheel]

I posted this question in another forum, but I am seeking opinions from actual frame builders. Is it possible to weld or braze an extension onto a fork steerer tube that has been cut too short for a particular frame? I'm talking about steel forks, specifically threadless ones but it could possibly apply to threaded ones. It seems like it would be possible to insert a steel sleeve inside the fork tube -- securing it by pinning, brazing, welding or whatever -- and then weld or braze on an extension to the steer tube to the desired length. The steerer tube could then be filed/sanded smooth and threaded if applicable.

This is a hypothetical question, mainly spurred by my curiosity after seeing so many used steel forks for sale with their steerer tubes cut short -- making them useless for larger frames. My curiosity is also sparked having seen so many nice vintage bikes for sale over the years that would have been perfect fits if not for the short steerer tubes.

If this is not advisable, please explain why. I know you can buy new forks or have them custom built. I am thinking about all of the piles of nice used forks that are unusable unless someone has a small frame or can ride with huge handlebar drops.

[Rody]

Yes, it's possible if done correctly.



I'd suggest contacting a builder in your area and discussing the possibilities with them (ie... please do not email/call me, I do not have time)

cheers,

rody

[Jonathan]

smart AND photogenic

[datas_brother]

Yes, even in CF but not financially sensible:

[dgaddis]

... but not financially sensible:

Even in steel I imagine it makes more sense fincanically to just buy a new fork.

[Amaro Bikes]

As they already said, if properly done, there's no problem, specially with steel. Carbon might be a bit trickier, and aluminium definetly not the best option as penetration might not be enough, in such case is quite recommended to reinforce the inside but bonding a carbon or metal sleeve, at least 50-50mm around the weld area.

Also, depends on the fork, but many times is possible just to replace the steering tube, wich is definetly the safer option of them all.

Cheers

[Bobqzz]

I did one about 10 years ago and it was no problem. I machined a plug, slid it in the fork, tigged it, and has been on the "ice bike" for the last 10 years.

[Tarwheel]

Thanks for the info. The scenario I have in mind is this. ... You find a nice used bike for sale, perhaps your "holy grail." Something like a De Rosa in mint condition, in an unusual color that would be hard to match with a replacement fork. You want to keep the original fork anyway because it was designed to fit the frame, but the steerer tube has been cut too short for your use. It might be worth the effort and expense in a case like to have pay a frame-builder to extend the steerer tube.

I actually passed on a beautiful De Rosa like this years ago. It was an unusual blue shade that I have seen only a few times. The frame was in nice condition, in my size for a great price. The only problem was that the steerer tube was cut too short for my fit, so I didn't buy it. You would probably never find a matching De Rosa fork to fit the frame.

[shirk]

Thanks for the info. The scenario I have in mind is this. ... You find a nice used bike for sale, perhaps your "holy grail." Something like a De Rosa in mint condition, in an unusual color that would be hard to match with a replacement fork. You want to keep the original fork anyway because it was designed to fit the frame, but the steerer tube has been cut too short for your use. It might be worth the effort and expense in a case like to have pay a frame-builder to extend the steerer tube.

I actually passed on a beautiful De Rosa like this years ago. It was an unusual blue shade that I have seen only a few times. The frame was in nice condition, in my size for a great price. The only problem was that the steerer tube was cut too short for my fit, so I didn't buy it. You would probably never find a matching De Rosa fork to fit the frame.

I assume you wanted to run spacers under the stem?

Just get a custom stem made to account for you fit.