Is this frame repairable?
 

I have an old EAI Bareknuckle track frame that I bought in 2006 back during the fix gear bubble. I rode it for a few years, until galvanic corrosion welded the aluminum Thomson seatpost into the frame. In my attempts to twist it out, the post snapped, creating a tear in the top of the seat tube. I have stored the frame ever since in the hope that it would make a good restoration project someday. Photos of the aftermath are attached. The remnant of the seat post is still in the frame, although I am sure I can remove it by chemical means.

My question is about whether or not the tear in the frame is repairable. The tear does not encroach on the weld with the top tube. I have always suspected that if the displaced portion of the seat tube were bent back into place and the tear welded, it should be fine as long as there was plenty of seat post inserted into the frame.

If it is repairable, does anyone know of a frame builder/frame repairer in or near NYC who might be qualified and willing to do it? The bareknuckle was an Italian made frame that back in the fixie bubble days was highly sought after, so it may be worth the effort and cost to repair rather than tossing it in the recycle bin.

https://cimg0.ibsrv.net/gimg/bikefor...2ac6413321.jpg
https://cimg1.ibsrv.net/gimg/bikefor...9f128f0ffe.jpg

That is a nasty tear! One option is to use (good luck finding one) a seat post that has its own clamping design and won't need the seat lug's binder at all. Think of a classic quill stem's wedge and draw bolt. Kabuki (pre Bridgestone) used one on their cast AL junctions and steel tubed bikes. Andy

Seems like it could be TIG'd back together and the cleaned up with a reamer - if it can be bent back and clamped reasonably. However, the collar is brazed on and might be negatively affected by the welding.

Some welders might feel more comfortable with this than a frame builder might, since welding torn steel is not a normal bike repair activity. But a good welder won't do it if it is a going to fail.

Basically toast I'm afraid. The crack could be TIG welded up and then the ST reamed, but as Kontact says, the problem is that brazed-on collar. The braze will melt into the weld and ruin your day. So you would want to try and remove that collar completely first. But that's going to be difficult as half of it is on a piece of metal that is already trying to fall off. If you could get the collar off (grinding/sanding is how I would tackle it) then you could reassess the situation and see how much good metal you had. It might be possible to squeeze it all back together around a seatpost, insert a new patch piece in the slot, weld it all up, recut the slot, ream it, and then use a collar that just sits on top. It would be fun to try to see what happened but I wouldn't have high hopes.

Exploring the seat post option already mentioned would likely be best. Cosmetically the tab could possibly be bent back and a binder bolt put in to make it look like it is doing its job. A good big welder would probably do just fine until they got to where the lug and tube are joined, then the puddle is going to become a hot mess.

If this was a sentimental frame so it was worth the effort, I would start by bending the ear back as best as possible. Next using a big rosebud flame, I’d remove the seat binder cluster. Shaping a piece of 1 1/4” OD with .058” walls to slide over the extended seat tube to just avoid running into the stays. This would take some blacksmithing. I’d drill a small hole at the end of the crack and fill it with brass. Silver the sleeve and brass braze a new binder.

Could you perhaps grind off the ears for the binder bolt and use an external collar? E.g.:
https://imgs.search.brave.com/AeYIx1...0pGVjhM/LmpwZw

Yes you could use one of those collars (or braze on another one). The harder part is getting rid of the one that's there and then patching up what's left.

Looks like it would be fairly time-consuming and tricky to repair the crack well. Time is gonna cost money - how much is the frame worth and more importantly how much is it worth in sentimental value to you ?

Sometimes the worst thing you can do is keep something like that kicking around, always nagging at you and reminding you of the seatpost misadventure.

After 19 years methinks it might be better to simply let this one go. Maybe put the expense towards a new or used track frame. Brooklyn Bike Jumble might be well worth a visit next year.

I was about the say melt off the existing brazed collar, but Doug beat me to it. Then I'd blacksmith the tube back down and braze the crack at the same time as I was brazing on a new pinchbolt fitting below the crack. With the new pinchbolt below the crack, the metal above and the crack itself would not be highly stressed.

I would repair this if it were my frame, because I'm a hobbyist and my time isn't money. But my cost estimate to do it for someone else would probably make them leave in a hurry. I don't like doing repairs, not as fun as creating something new, so my cost estimate is more or less intended to make them leave in a hurry. Although I'm more likely to want to do it if all the paint is off already. It's mostly the paint that makes repair work nasty. Oh and I'd want the seatpost out already, looks like it's still in there? I know how to get it out, but it's a bit unpleasant so I'd charge plenty for that.

Seems like (I could be totally wrong) if you could get off the collar, bend the tube back and then cut 1cm off the top and solder the collar back on and lower the slit. The collar will will cover 3/4 of the crack while keeping the original parts, so it should be strong enough. After cleaning up the silver the crack should disappear under the paint.

Just an idea to keep things simple.

I was going to suggest a weld, but it’s in a spot that needs occasional loosening and tightening and that’s not going to make the weld fix happy long term. As well I’m not seeing a collar in that spot, I think the frames done and feel for you as I had a Klein Quantum fail in the same manner. Had to replace the frame.

A weld ought to be just as strong as the original metal. A little bit less in this case if you sand it completely flush just because the filler rod is (usually) mild steel and not cromoly. But I wouldn't be concerned about occasional tightening and loosening. But as discussed I do also think this is a difficult repair.

Not a frame builder myself, but also not wanting to give upon an otherwise nice frame, I would go with the suggestions above: totally grind off the top lug / binder and fabricate or buy a longer lug/binder which covers the crack entirely.
Can one re-braze the longer lug on there?

oh, if only i was a frame builder and knew what i was doing or talking about...
My Jamis 'Sputnik' suffered a very similar fate, but the crack/tear is much smaller and in a less crucial area of the seat tube,
so far i have just ignored it, but keeping an eye on it..