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  for Metal Finishing since 1989
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Sweat destroying aluminum parts on carbon bike

I am a bicyclist, and my bike is constructed of carbon fiber. The rear dropouts, where the rear wheel clamps onto the bike, is made of aluminum, and ends of these slide into the hollow carbon tubes. I sweat profusely when riding, and I think that my sweat is destroying the dropouts. They are covered with a white substance, and are even swelling.

They are swelling to the point that they are starting to split the carbon tubes that they are places inside of. Is there anything that I can do to stop the oxidation (if that's what it is), keep it form recurring, and reverse the swelling? This is a very expensive bicycle, and I hate to lose it to something like this.

Thanks,

Kelby Kennedy
- St. Albans, WV USA
2005

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If the sweat is indeed the problem, anything that prevents the sweat from reaching the parts would help.

Use the search engine to find some letters on how to clean and polish aluminum, and remove as much of the oxidation as possible. Then, look into a lacquer or have the parts anodized or keep them oiled or paint them with a high quality paint.

Good luck.

Jim Gorsich
Compton, California, USA
2005

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This looks like an impact issue, every time you hit a bump in the road it's like hitting this area with a hammer and the metal spreads, the paint is peeling because it doesn't flex with the spreading metal, and that would also explain why the carbon fiber tubes are splitting. I would suspect that a bike like this has a specific purpose(like racing on a track, not training or daily riding). I doubt sweat has anything to do with it. I would go back to the manufacturer and ask them about it.

Sheldon Taylor
supply chain electronics
Wake Forest, North Carolina
2005