Snake8

Hey all,
Was doing a drivetrain clean last night and noticed what I thought were chain nicks are really metal flaking off of the chainrings. Subsequent inspection of other parts found some flaking metal on the brifters and the front derailleur. It looks almost like it is a surface layer of metal being rusted or otherwise corroded like you might see happen to aluminum when it 'rusts'. All parts are Dura-Ace probably 5 years old. Nothing looked like it was going to break, and I've definitely got a lot of miles on these parts, just wondering if anyone else has seen this...

Thanks.

jsharr

Have you used Simple Green as a cleaner? It has proven to be very corrosive on metal parts.

jsmithepa

Either that or u live near a chemical plant.

caloso

I have that same issue on my front derailleur cage. I think JSharr is right: I used to use Simple Green. Now I just use Dawn and warm water.

There's no performance degradation, it just looks crappy.

Snake8

Hmmm, no chemical plant. I use Pedro's Citrus degreaser. I know when I rode down in Central America the soil was very alkaline (I think) and we had some issues with corrosion, but have never seen this on any of my bikes around here. Yeah, no performance issues, just wondering what the cause might be, maybe I'll stop using Pedro's...

JiveTurkey

This is very good to know. I'll stop using the stuff. Here's an old BF thread I found some may find interesting:
https://www.bikeforums.net/bicycle-mechanics/4117-simple-green-alu.html

operator

All the chemical degreasers are toxic anywyas, despite whatever the hell is claimed on the lable. I just read the warnings on the Pedros "foaming bike wash". One of the warnings was: do not get on skin.

Seriously?

Mild detergent diluted will work fine. If someone has an even less toxic/natural combination, please let me know. I'm all ears.

jsmithepa

It may not be flake, but simply chemicals etching into the finish. Try some metal polish see what happens.

Expensive parts should not look crappy.