Hello I was given this frame from a charity location as I had given them three road bikes.Their comment was see what you can do. The problem is that there is a crack in the headtube which can be seen in the close up photos. I have marked the crack above and to the right with a marker pen.
Thoughts have been to have this tig welded??and a local engineers shop will do this for £15.
Would you ride this bike as I do not do mountains but stick to roads or paved paths.Would it be better to keep/ display as an ornament????.

I doubt if any repair would be any good. It's at high stress point where the fork and head tube has the greatest amount of impact going over varied terrain, such as bumps and holes.

toast

If you know someone who really loves to tinker, they might be able to make a new headlug. Sounds like a fun project with a low chance of success.

What is that frame? Very interesting.

Is there any chance that a Vitus or Alan head tube could replace it?

If the Aluminum was heat treated, you can forget about Tig welding. You can try drilling a stop hole at the end of the crack then laminate the whole headtube with carbon fiber.

Uhmmm.."cross" frame??.....I wonder if it was crashed, causing that crack and maybe destruction of it's fork. What's ironic is, it would probably have been more repairable (by outfits like Calfee) if the damage was with it's CF tube(s).
It's a nsaty crack that already went two directions. I say it's toast....but there are really interesting details on that frame that it will make a nice wall ornament.

$23 bucks U.S. to weld....If it can be done, why not try? I went out to eat with my family of 4 last night to Fazolis and dropped $35 bucks. I would form a aluminum collar and weld that in place. Maybe because I have access to an aluminum welder and the materials do do it my opinion is skewed.
I don't know that frame maybe it's not worth the time, but it's all about how much fun it would be to fix.
I guess sometime I just choose to walk down the other path. Have Fun!

I'd suspect that you'll have to remove the cf tubes before welding the headwork.

Is there any chance that the frame maker has a replacement option? With that type of damage I'd be concerned about hidden cracks.

Personally, i cannot envision a repair in this
circumstance that I would ride. Thus, I would
not either put someone else on it.



Perhaps I am too conservative with regard to
these sorts of frame materials, but I have
been increasingly aware of late of the large
number of threads similar to this in nature
(Aluminum frame-- crack in head tube or
other high stress area -- how can I fix and
ride it?)

One of the deals you accept when you make
your bike from aluminum is that it will eventually
need to be retired, like old aircraft made of
similar lightweight alloys and for the same reason.

I shall no doubt hear voluminous disagreement
from people with other opinions. I believe I
have the bulk of materials science on my side.

Cool frame!
But toast unless you can get the head lug replaced.

I agree

I think its less a matter of if you can fix it and more of a question of how safe you'd feel riding it

Cool looking frame, but I don't think it's worth a potential faceplant due to the crusty old aluminum.

You would need to un bond the Carbon from the aluminum before welding, perhaps add a steel reinforcing collar around the outside and then re bond. Not worth the effort an cost to do properly. If it were welded assembled the heat would likely damage the carbon or it's glue. The collar might work by itself with a stop hole in the crack, but I would not ride it.

Its a cyclo cross frame, and even I would admit that would be dangerous to ride.

I think a collector would be intrested in a strange bike like that, even more so if you could find the forks.

I'm sure you're right and I would not ride that frame no matter who said he could repair it. Anything going wrong on the front end of bike is a disaster: even a zero-speed crash (like getting a shopping bag fouled in the spokes as happened to a woman I know) throws you to the pavement so hard it can break your face off your skull and nearly kill you.

But how is that really old aluminum aircraft like DC-3s are still able to fly safely? I know they get treated really gently and lovingly by their owners but still....they've outlived most of the people who were born when they were built. Then there are the B-52Hs that are still racking up millions of flying hours on active service 50 years after the last one rolled out of Boeing's factory. Do the aluminum airframe components get replaced?

Really cool frame! What is it?

i'd have it repaired and ride it.

Vintage aircraft are subject to periodic overhauls to keep the airframe from failing. Vietnam-era helicopters still in use in the military have been completely stripped, rivets drilled out and replaced, engines completely rebuilt and all components inspected periodically.

The analogy between bicycle frames and airplanes, while
still valid I think, is a little too strained for me to belabor it.

DC-3's are a unique case, and the ones still flying owe the
fact to a huge number of militarily surplussed aircraft for
parts scrounging, a generally rugged and simple to repair
design, and a slightly different definition of "safely".

https://en.wikipedia.org/wiki/List_of...lving_the_DC-3

I have no doubts at all that 50 years from now there
will exist a hard core cadre of "classic aluminum framed"
bicycle lovers who will be arguing ad infinitum with regard
to the best way to repair something like the frame here
in question. Each to each, de gustibus non disputandum.

I can think of one possible way to make it rideable. Is the head tube 1 1/8"? If so, you might try TIG welding the crack to impede it from further propagating.
Then press in a steel sleeve into the head tube, compression fit. The steel sleeve in turn makes it a 1" head tube and use an appropriate 1" fork to make it 'rideable'.

Wow. That sure answers that question. Yikes.

Does anybody know someone, or know how for that matter, to bond the carbon tube back into the lug? I have a Vitus Carbone frame that has a seat tube that has separated from the BB lug.

"Guywires" in Canada were known to be specialist of the brand and IIRC, repaired Vitus frames too. They're still around actually, but I think they scaled down their business. Shoot them an email and see if they can stil do reapairs. They actually returned my emails last year when I inquired about Vitus Carbone decals. Otherwise, maybe Calfee can also fix tube lug separation problems.

Chombi