Terzot

Hey guys, recently bought this bike, didnt really know about crack. So i decided to reapair it. I visited local specialist who use to weld well in aluminium. He choosed a proper alluminium alloy and welded it.
Glue didnt come out.
Photos and videos:

Cant put an URL so please replace "+" with "." To see photos and videos from repairment.

instagram+com/p/B2r45vkiAPU/?igshid=1uv2ibwpq33j6



Can you tell me if its safe to ride it? I know not professionally, but for 10km daily rides?

If not how much can i get for the parts?

(Shimano 600 brakes, cinelli handlebar, front campagnolo, rare shimano 105 deraillaur, mavic ma2 wheels ( new tyres, rare with campagnolo hub), surgino might crankset with gipemme pedals.


thanks for all answers.

Terzot

Cant put an URL so please replace "+" with "." To see photos and videos from repairment.


instagram+com/p/B2r45vkiAPU/?igshid=1uv2ibwpq33j6

CliffordK

@Terzot's album on BikeForums.

https://www.bikeforums.net/g/user/506604
https://www.bikeforums.net/g/album/15341421

CliffordK

Your two Instagram links appear the be the same as the first photo above.

Looking at your seat cluster lug, it isn't immediately clear about where the repair is. Perhaps on the top/front side of the lug?

There is no real answer to the safety of your frame. Some people have successfully welded ALAN or Vitus frames. But, others are leery about them.

You have a few potential issues. First of all, you likely affected the bonded joint between the seat lug and the top tube, and perhaps all the bonded joints on that lug. So, the glue could be destroyed, if the lug wasn't completely removed and rebonded.

You could also have damaged any heat treating of the tubes.

Also, several cast aluminum alloys are considered problematic for welding.

10km a day? 70km a week?

• Fast?
• Slow?
• Technical hills and descents?
• Solo?
• Rider Weight?
• With a group?
• Do you have anybody that would give you assistance if you need it?

You could be putting quite a few miles on the bike and frame.

How diligent are you with maintenance and observation?

I'd consider riding it, but also pay attention to sounds, popping, watch for cracks, etc.

Also I'd do it on moderate flatland rides. No heavy loaded touring rides. No technical mountain descents.

Also keep rider weight within reason. No 200 lb+ riders.

Oh, another final note. The company ALAN still exists. You might verify what kind of bonding they would have used on that frame. There are brands that used a pressed/crimped interference joint. That may be less dependent on glue, but still may have issues with welding heat cycling and expansion.

Rajflyboy

Nice bike

I’m sorry to hear about the crack. I agree with Clifford on his thoughts about this situation.

Terzot

Thank you very much for reply. So basiclly during welding there was some glue leaking out from the horizontal top tube. Not much but definetly some. So the specialist not only welded the hub(element connecting tubes) but also managed to put connectivity betweem hub and tube.

About riding: its just slow rides in the city, nothing really special. There is only one 30m hill , and then the road is flat.

I will pay big attention to any sound, just love the way it rides.
Rider weight: 185 lbs
I will try to post more videos and photos in my profile here so you could see how the reapairment went.

CliffordK

I went and added your third photo above.

It may also depend on the welding method. Aluminum doesn't like weld contamination. It is also, however, possible to braze aluminum at a bit lower temperature, and working with several different alloys.

A very unique bike is the "slingshot bike".



I've never ridden one, but I think they did go into at least a moderate number of commercial production. But, the point is that the top tube is under compression while the downtube is under tension under normal riding conditions. There is some shift during extreme conditions such as a crash.

However, the normal riding forces would tend to hold your bike together.

You likely have some weakening of the joints around the seat cluster, but it may not be as bad as one might otherwise think.

Atlas Shrugged

Coming from a metalworking background I would say the frame is not repairable and unsafe. Any attempt to weld would cause the epoxy holding the frame together to breakdown and be rendered useless. It looks like it could be tig welded however to get a full penetration weld you would need to prep the crack most likely by grinding a bevel into the lug and layering the aluminum into the opening. The issue is the alloy is unkown and most likey it would quickly crack along the sides of the weld. Effects on the underlying tubing would also be unknown but if temper in the tubing is removed by the heat of welding it will soften substantially think aluminium can soft).

Relying on the frame to stay together because it is under tension is crazy in my opinion. If it's not safe and reliable don't ride it.

3alarmer 

.
...this is commonly how these frames have failed over the years. No, it's not safe to ride it, and the only reliable repair would be to remove the cracked lug, and replace it with a new one using a similar preparation for bonding and bonding adhesive as was used in the original construction. It's a question that comes up a lot...more over in the C+V forum.

I think I once saw a reference to a company that did these repairs on these frames, but I don't recall the name of the company, nor do I know if they are still in business. I suspect that even if available as an option, it's not cheap. Any welding on the lug has essentially destroyed the adhesive.

The wheels and the Cinelli bar are probably worth 150 bucks, if they are in good shape.

Wilfred Laurier

That looks like it will make some nice wall art, but it should not be ridden.

The argument above, that the frame will be 'held together' by normal riding forces is technically correct, but not a complete answer. While the top tube is not likely to fall out, if the weld or glue or both fail, the tube will not be held in place and will allow significant movement, which will result in excessive flex and movement at the other joints in the frame, which will almost certainly lead to failures of other joints or lugs. That bike was designed to be ridden with all joints intact, and if one or more is not then the frame will be unstable. It may result in loss of control, or it may seem fine until another part of the frame fails and it slams you to the ground in front of a bus.

It's a pretty bike, but should not be ridden unless you can find a new lug and bod the thing back together as it was originally intended.

Homebrew01

If I were TIG welding that, After grinding out a bevel, I would do a series of spot welds, letting it cool between each one, to minimize heat buildup that would affect the glue.

Andrew R Stewart 

I have to say that if one were to risk a main frame failure having it on the seat cluster would be my choice. Far nicer a result then, say, the lower head joint. Andy

Hiro11

Yeah, there's no way in hell I'd ride a vintage aluminum frame I knew to have a catastrophic lug crack.

Darth Lefty 

Oh but what a pity to lose those amazing decals.

I too remember someone posting in C&V about ALAN frame repair

CliffordK

No idea what brand, but I had an acquaintance, probably when I was doing post-bac studies in the early 90's with a bonded aluminum frame and broken rear dropout. And, I'm pretty sure he had it welded without thinking twice about it. And, survived as long as I knew him (heading in different directions in life wasn't due to frame failure).

Hmmm... an internet search, and it looks like he may have survived and may be working for Intel up in Portland.