Aluminium Frame Repair - Please Help!

[KermitGKona88]

I tell you what send it to me and I will be happy to test ride it for you for say 7-8 months and let you know if it gets any worse

 

[rosstheboss]

Kind of hard to tell, but is that where a front mech has been attached?

 

[Barneyballbags]

Kind of hard to tell, but is that where a front mech has been attached?

The front mech mounts on to a bracket. The crack is at the top of the seat tube

 

[Elev12k]

I bought an AlMega XT about 6 years ago. It looked really like new. No rim wear, the little cilindric bits still on the tires etc. At home I discovered the tail was cracked at multiple places. One crack ran all the way round the seatstay. It wouldn't surprise you I considered the frame toast. The aluminum quality can't be trusted and it would not have been wise to further invest.

I donated the frame to a collector-friend and the XT group found its way to my undestructable Panasonic e-stay.

 

[jamabikes]

i would scrape the paint off and have a look see. wouldn't worry about being too neat getting the paint off as it is always easier to spray a whole tube rather than just a small area. bit strange having a two way crack. if it is cracked then drill the ends of the crack and run a long seat pin and keep an eye on it.

 

[shogun]

I'm going to bet its just cracked paint.

Get someone with a boreoscope to have a look down in there.

A what now?! Who would have one of them?

Sounds painful!

Boroscope or Borescope, many mechanics and engine rebuilders will have them on hand as they're commonly used to inspect inside engine cylinders without major disassembly. The best one here would probably be a rigid boroscope, it is a straight tube with a lens and eyepiece, normally with a outer casing of optic fibres which illuminate the area being examined.

Just poke it in and have a look from inside.

 

[boy"O"boy]

Is the alu cracked or could it just be the paint? If it is nos, I can't see how it would have cracked the alu, as that's a way down the tube and protected from storage type damage.

The trouble is, 1991 Al Megas are notorious for cracking, and specifically on the seat tube and under the head tube, which is why I immediately thought the worst!

The seller described the bike as "virtually NOS". It's definitely been used, but I'd say only a handful of times at the most. The only signs of use are the marks on the seatpost from where it's been adjusted, and the chain marks on the chainrings.

I'm going to sand the paint back around the damaged area (gulp!) at the weekend, so I'll be able to see for certain whether it's paint or metal damage. Hopefully the former, but if it's a crack in the frame then I'd like to get a few repair options together, so that I can present them to the seller.

Just read your post in Readers bikes M. - What rotten luck. - had been hoping for some great pics after yesterday's pre - receiving build up. You're right though, 1991 Al Megas are notorious for cracking. There are probably fewer of these left in original colours due to repairs and scrapping than the total number of dolomite Kleins!

Right. If you're going to strip the paint in a localised area - whatever you do, don't use an Angle grinder! Nitromors and fine wire wool should be fine but be patient! There were quite a few layers on there when I stripped mine back to bare bones.
I know someone that recently did a full Al-Mega DX resto so hopefully would be able to colour match the pearlescent white where the damage is ( if it is a crack )...only one way to find out though!
Matching the fluro for the other scuff may be a bit harder though. 20 Y.O fluro must have had some fade over that period. PM me and we'll try a sort something.

Cheers.
boy"O"boy

 

[Barneyballbags]

Rest assured, there won't be an angle grinder in sight when (if) I strip the paint back! As for the fluro, it hasn't faded one bit by the looks of things ...

In hindsight, I really shouldn't have taken the chance on buying the bike in the first place, especially as it's come from overseas, making a refund/return a lot more difficult.

But hey, we all know what it's like when we just have to have something!

 

[Barneyballbags]

Boroscope or Borescope, many mechanics and engine rebuilders will have them on hand as they're commonly used to inspect inside engine cylinders without major disassembly. The best one here would probably be a rigid boroscope, it is a straight tube with a lens and eyepiece, normally with a outer casing of optic fibres which illuminate the area being examined.

Just poke it in and have a look from inside.

I like the sound of that to begin with - definitely more attractive to me than stripping the paint away. How easy would it be to see the crack from the inside, if there was one?

 

[Elev12k]

In hindsight, I really shouldn't have taken the chance on buying the bike in the first place, especially as it's come from overseas, making a refund/return a lot more difficult.

But hey, we all know what it's like when we just have to have something!

Don't know what you paid for it, but when my Almega XT appeared to be toast I still had the excellent XT parts and it enabled me to finish another nice project. DX is also very nice kit, so you not end up with empty hands and it opens new opportunities. The frame is distinctive and look mint, so it could act as terrific item for display purposes.

Alternatively you ride and see how long it lasts. Or you have it repaired in some way and see how long it lasts.