[Rik]

Heya... so this bloke walked into my work today, and put half a bike on the counter
it was an old klein with 105, syncros and profile goodies
and he said "i'm chucking this out, but was thinking yuo guys would have more use with it"

i was ecstatic
but, after close inspection i noticed that the paint was "bubbled" and there was significant corrosion along a quater of the frame
the paint flaked off, and there was alot of white powder between the paint and the hard metal (i havent snorted the powder to test it yet but i'd say its alu-oxide)

what does this mean? the powder is a few mm deep... would the frame be rescuable? is this only a surface thing or would it be so damaged its unrideable?
i'm thinking about getting it resprayed... but gotta make sure its worth it first

 

[gtbike]

You say the corrosion is a few millimeters thick? If it's one millimeter it's way too much. This bike has been subjected to salt water or some other corrosive. My main concern is the part of the frame that you can't see, the inside. Without having the frame in front of me, if the corrosion is that bad on the outside then the inside is probably worse. A lesson to all owners- steel,alum, or otherwise- check the drain holes when washing, unplug them if nessecary, use compressed air to blow it out and spray in WD-40 liberally. This also is a good practice before winter storage. Anyway, the frame is most likely junk and I wouldn't want to be the rider that finds out!

 

[johnbryanpeters]

He said the oxide was a few mm deep, not the pitting.

Get one of those cheap sandblasters that looks like a spray paint gun. Fill it with baking soda and blast away the Al2O3 and bubbled paint, and make your own decision. The baking soda won't harm the unoxidized aluminum (nice for cleaning carbs too...).

J

 

[Rik]

Originally posted by johnbryanpeters
He said the oxide was a few mm deep, not the pitting.

exactly so
the oxide is bubbled up, but when you scrape it off the tubing isnt pitted at all

i spoke to a framebuilder today, i'll get him to inspect it and respray it and i'll have myself a beautiful light bike

 

[gtbike]

Hell yeah. I thought the frame was eaten a coupla mm's into the tube. If not, like JBP says work it and good luck. And I thought I was the guy with the baking soda to the carbs trick. It works great!

 

[iepeulas]

The frame is aluminium??? If thats the case, Its not aluminium oxide, Its been exposed to some strong oxidiser, because the aluminia (thats Al2 O3) is very unreactive, and air tight preventing further oxidation of the metal. Now if was exposed to something a little more virulent, say some acids or sodium hydroxide, that could account for this high degree of corrosion.....

 

[Rik]

today i got a wire brush and rubbed down the paint
heaps of powder everywhere! it smelt like chlorine... at first i thought it woulda been sweat from home trainer use... but, my investigations proved otherwise
the aero bars gave away the fact it was a triathlon bike, so all that powder woulda been salt from the pool

the metal underneath isnt pitted at all, so its getting repsrayed this week and built into a sweet bike

 

[iepeulas]

Aluminium chloride is white........