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What do we think to this? Corrosion of the aluminium drop-outs of a 2010 Specialized Tarmac.
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Superficial/cosmetic?
Terminal?
Spesh have a lifetime warranty on frames, but say corrosion is excluded, which seems a bit odd.
"We stand behind our frames, forever" (but we expect them to simply rot due to the passage of time if exposed to water and oxygen)
Meh. Powder coat and carry on.
Alloy corrodes it's just what it does it looks worse than it is. Probably.
but we expect them to simply rot due to the passage of time if exposed to water and oxygen
Salt. They have no control on the conditions it's ridden in so they don't gaurantee it.
They have no control over anything i do with it, but salt exposure is pretty easy to predict.
Are you sure it's not the vibrations from the noise of the hub that have shattered the paint? 😉
Seriously though, it's just surface corrosion on aluminium, I wouldn't worry about it.
Galvanic corrosion.
As the dropout corrodes it expands, and then damages the tubes/ stays.
They have no control over anything i do with it, but salt exposure is pretty easy to predict.
Exactly they predict it will happen, it's aluminium on a road bike. So they don't guarantee it because any protection from paint, anodising or powder coating is only good until it scratches to metal.
It's a what? 12 year old bike frame? Go and look at a similar aged Volkswagen, you'll see a bit of crust.
Galvanic corrosion.
As the dropout corrodes it expands, and then damages the tubes/ stays.
If it snaps, what's the worse that could happen?
It's corrosion but I'm not sure it's galvanic. Where is the dissimilar metal to act as the cathode?
It's really hard to tell from the photo but you could make a judgement based on how pitted the metal is in that area. It should be fairly chunky around the dropout and if there isn't any metal loss you'll be fine. It may just be that the paint around the dropout has been damaged and because only a fairly basic cosmetic coating has been used it has started to suffer from (under) creep and the paint has flaked off. Same mode of action but failure of the coating is equally likely around the weld as it creates stress in the coating. Clean it up, remove loose material and touch up with a rattle can. You'll probably be fine*.
*you might die, this is not my fault.
What do I think?
I think you should have cleaned it and touched it up with paint long before it got to that point.
What do I think?
I think you should have cleaned it and touched it up with paint long before it got to that point.
What SOM said. That what you have there is years of neglect. Your corrosion cell is forming under the lifted edge of the paint coat & moving outwards in all directions. IE, left untreated that is going to be worse next year. Galvanic corrosion can form due to the very slight dissimilarities between parent metal & the filler material. Can't comment if that's the case here. Looks to me like the coating has lifted & corrosion has got underneath.
It looks like the worst affected area is on the drop-out. I'd clean that up & have a look round the weld with a magnifying glass. If there are no defects it could be cleaned/primed/painted again.