Tips for aluminium welding in Gotebörg

[Moises]

Hej!
I got a crack on the headtube of my sons aluminium bike. I got it second hand so I can't or want to contact the manufacturer. I'm instead thinking on fixing it.

Can anyone recommend a workshop where I can go to repair my bike?

Mvh

 

[VCN]

I have no idea. But I love the way you spell Gotebörg! :D

 

[Q&D]

Could you please upload a picture of the crack?

 

[Moises]

Whoops, ursäkta alla göteborgare för det... ;-)

 

[Moises]

Here comes a picture of the crack

 

[dabac]

That kind of damage is generally considered unfixable.
Aluminium alloys used for bikes tend to need annealing after welding to reach adequate strength.
And even with a good enough weld, the root cause of the damage is probably a too tight bearing seat, which would probably have degraded even further from welding distorsion.
So you need someone to ream the bearing seat back to spec too.

I've fixed a bike with a considerably smaller crack by cutting a steel collar on a lathe, then press-fitting over the headtube, squeezing the crack shut.
I've toyed with the idea of wrapping damaged tubing in CF. A 2 mm thick CF sleeve should add plenty of strength and hopefully prevent catastrophic failure.
Some daring souls have reported using U-clamps and even hose clamps to keep bikes damaged like that in use.
An U-clamp - if sized right - might just work, but I wouldn't trust a hose clamp.
Since it's not you who'll be riding it, cut your losses, get another bike/frame.

 

[Moises]

Thanks a lot for your answer.
Wrapping the head tube in CF seems a secure enough alternative but I think I'll just buy a new frame instead. At the end of the day this is my sons bike and I can't even imagine the idea of him getting hurt due to daddies home fixed bike...

 

[trailbiker]

Selling crack in Gothenburg? This thread could be fun.

 

[Fältprästen]

Wrapping the head tube in CF seems a secure enough alternative

I did that with my mothers bike. The crack was at the opposite end of the headtube. I used CF roving and wrapped it around the tube several times in combination with epoxi. So far a success.

 

[Q&D]

Here comes a picture of the crack

I would not fear that crack.
No severe failur could occure. The moste dysfunktion would be some play when front wheel braking, but probably not.

 

[Preacher]

I would not fear that crack.
No severe failur could occure.

Nice advice.