Is it possible to "extend" a cut steerer tube?

[dawgie]

Someone is selling a used steel fork that is from the exact model and color as one of my bikes. My bike has a 1" threaded fork and this one is 1-1/8" threadless, but it will fit my frame because it has a 1-1/8" head tube. (It has a reducing headset.) I would like to buy the fork except for one problem -- the steerer tube is cut too short. Would it be possible for an experienced frame-builder to weld or otherwise attach a 4-6 cm extension to the steerer tube of the 1-1/8" fork if I bought it? A new fork for my frame would cost $300. I can buy the used fork for about $100. Obviously I wouldn't want to spend $200 getting the fork tube extended.

[93legendti]

Threaded to threadless adapter?

[christian]

In a safe way that a professional would do? No.

Possible, sure. Take another tube with an OD that matches the ID of the steerer. Braze it in. New steerer above that, braze it on. Hope it's straight enough that the headset won't bind.

Oh yeah, this is a bad idea.

[Bruce K]

I would try asking Kelly Bedford, Mike Zanconato, or someone like that.

I can't see why it couldn't be done, even with a minimal sleeve or small internal lugs to ensure that it is straight.

BK

[Louis]

Nearly anything is possible (I'm thinking a machined part that could be brazed into place with an OD on the lower section that would match the ID of the steerer tube, and an OD on the upper section that would match what's needed for the HT and headset) but it's probably not worth the cost, hassle, or risk of potential failure at the step radius.

I'd stick with what you have now or get a whole new fork.

[dawgie]

I would try asking Kelly Bedford, Mike Zanconato, or someone like that.

I can't see why it couldn't be done, even with a minimal sleeve or small internal lugs to ensure that it is straight.

BK

This is what I was thinking. With an inner sleeve, the tube extension should line up properly for welding or brazing. Then it could be filed smooth.

There are a ton of used forks for sale on eBay that are essentially useless for many bikes because the steerer tubes were cut short. It seems like this would be a good way to salvage an otherwise useless fork.

[Louis]

It seems like this would be a good way to salvage an otherwise useless fork.

$ and risk of failure are two reasons I wouldn't do it.

[christian]

Don't waste frame builders' time with questions like this, honestly.

[pbarry]

I've seen Bay Area frame builder Bernie Mikkelsen do this: First, he cut the steering tube down on the original fork so a quill stem would not bottom out on the repair. Machined a 3" thick wall chrome moly insert, then knurled the insert so it would have a decent press fit, and hold the silver. Insert was fit into the fork steering tube, and extension, then brazed. I was impressed and would have ridden the fork without qualms. You'll have to find an old school FB to do this, one who's used to doing repairs. Took Bernie less than 15 minutes.

[cogclog]

For $20 you can get one of these... http://www.wiggle.co.uk/bbb-bhp-22-steerer-tube-extender/
Not pretty but gets the job done.

[dawgie]

$ and risk of failure are two reasons I wouldn't do it.

So, are you not worried about the welds failing on your frame as you ride down the street? Why would welding a steerer tube be any different?

[dawgie]

For $20 you can get one of these... http://www.wiggle.co.uk/bbb-bhp-22-steerer-tube-extender/
Not pretty but gets the job done.

A clamp-on extender would not work in the case because the steerer tube would barely clear the headset on my frame, so there would not be enough tubing to attach the clamp.

[Louis]

So, are you not worried about the welds failing on your frame as you ride down the street? Why would welding a steerer tube be any different?

Different animal.

There's been lots of testing on my frame (both by the manufacturer and by everyone else who bought one and is riding it) so I can be fairly confident that the design and manufacturing are good. What you're proposing is a one-of with all the attendant issues that brings.

Why take the chance?

[dawgie]

Don't waste frame builders' time with questions like this, honestly.

Why would this be any different than "wasting" a builder's time fixing a broken drop-out, brazing on a pump peg, etc.?

I'm hoping some frame builders can chime in.

[echelon_john]

Because it's the single most critical tube/joint on the bike to the rider's safety?

Honestly, this doesn't make sense. The only way to safely do what you're asking would be to remove the steerer from the crown and braze a new steerer in. Even if this were advisable, it would ruin the paint and you'd be in for a new paint job.

Any credible builder can build you a fork for your frame, painted to match the color you need, with fewer headaches and comparable cost to buying the fork and f-ing with it.




Why would this be any different than "wasting" a builder's time fixing a broken drop-out, brazing on a pump peg, etc.?

I'm hoping some frame builders can chime in.

[rustychisel]

Dear OP, I think you knew the answer before you posted.

"With enough money anything is possible".

The limiting factor is you don't want to spend the money. I understand that.

[dawgie]

Actually I was more curious than anything. My bike has a fine steel Waterford fork, which probably cannot be improved upon. I am curious because you see so many otherwise nice steel forks going to waste because someone hacked the steerer tube down to a short length. It seems like such a waste.

I could buy a brand new Soma steel fork for $100 that is probably 90% as nice as a $300 fork. I just hate to see good parts going to waste.

[rustychisel]

Well funnily enough I'm on the lookout for a small 1in threaded steel fork for a friend. We don't want an elephants trunk where the stem goes... I have a suitable candidate but don't want to cut it down to his size.

[buldogge]

Not exactly the same thing...but...we used to lengthen (or change configs) on Vespa and Lambretta fork steerers (~32mm) all the time.

We would machine a plug/insert and also cross drill the fork tubes either side. We would turn a chamfer at the fork butts and then TIG the two and TIG again at the cross drillings.

-Mark in St. Louis

[BobbyJones]

You people would never make it in a third world country. :rolleyes:

[rustychisel]

You people would never make it in a third world country. :rolleyes:

I live in a third world country. Yours is fast becoming one.

What's your point?

[Fishbike]

Short steerers are not "going to waste" just because they can't fit a certain (yours) frame. Like so many bike parts, including frames, you just need the right size for the job.

Get a new fork. There are better ways to save a hundred bucks.

[dawgie]

Ahem ... Yes, the answer is that it can be done.

http://www.youtube.com/watch?v=HNbJ9dadNYo

[christian]

You people would never make it in a third world country. :rolleyes:The question isn't whether it can be done. Obviously, if you damage the steerer of your DL-1 and you need to get to market in Assam, this is a logical repair - finding a suitable replacement fork is difficult, local repair is possible, and the thick gauge of materials make such a repair safe. None of those things is true on a "modern" race bike. It's, in short, a waste of time and effort.

Ahem ... Yes, the answer is that it can be done.You can wear your underpants on the outside too.

[christian]

Honestly, this doesn't make sense. The only way to safely do what you're asking would be to remove the steerer from the crown and braze a new steerer in. Even if this were advisable, it would ruin the paint and you'd be in for a new paint job.
Even that's not advisable. Given the amount of heat you'd have to put into the crown to release the steerer, the fit of a subsequent steerer would be sloppy at best. Sure, you can glop in more brass to take up the fit, but it wouldn't be as good as a new fork.

[cfox]

If you're lucky, no credible builder will agree to do this for you, and if they do I hope they quote you $201. Sorry, it's just not a good idea, especially for a delta of, what, maybe $50 or $100 bucks (I'm guessing no one would do this for less than $100, if they agreed at all)? Cut out one, small daily expense and you'll have your $100 back in no time.

[christian]

cfox - Rody's answer across the hall said it all. "Yup, it's possible. Don't call me." :)

[keevon]

I had a friend do this with a steel-tubed Lemond carbon fork. Although I don't think he bothered to put in the reinforcing tube... simply welded an extension to the steerer.

I don't ride behind him when he's on that bike.

[BobbyJones]

It was a tongue-in-cheek compliment to the ingenuity of those in areas of the world who do not have every option available to them.

Happy Friday.

I live in a third world country. Yours is fast becoming one.

What's your point?