Galvanic Corrosion on Aluminum Insert with Carbon Seatpost

Discuss light weight issues concerning road bikes & parts.
User avatar
Calnago
Posts: 6003
Joined: Sun Nov 07, 2010 9:14 pm

by Calnago

Yes, I don't think silicone grease is anywhere near as "adhesive" as Morgan Blue Aquaproof Paste. I still use a copper based antiseize for stuff like threaded bottom brackets. Just because I've had bottom brackets that I've removed after a very long time installed once with copper based antiseize and they've come out as if they had just been put in. So, I'll use the MB stuff to prevent oxidation (coating of skewers, etc)., and waterbottle screws etc., but I've also used it to PF30 cups as well on some Cannondales and so far so good. The copper based antiseize stuff is great but sheesh... you touch it on something and it takes forever to clean off, especially matte finishes.
I also used the MB Aquaproof Paste in installing the pressed in Ultratorque cups in my C60. I also tried it in lieu of carbon assembly paste in a Trek Seatpost clamp, but it acted to much like a lubricant there, so I cleaned it off and used Tacx Carbon Assembly Paste instead. But overall, I'm liking the stuff. As to the price, that little tub I got will probably last me my lifetime, so I'm not too concerned about the $25 it cost, as I still don't think it's the same as silicone grease.

@youngs_modulus... how is galvanic corrosion different from oxidation? The Morgan Blue stuff sure does seem to coat well, and sticks like crazy, hence you could never use it as any kind of bearing grease, which they specifically state. I ask because you are right, they don't specifically mention galvanic corrosion and I just sort of assumed it would work for that, since it's certainly recommended for those types of applications (pressed in headsets, seat tubes, etc.).
Last edited by Calnago on Fri Jun 16, 2017 9:59 pm, edited 1 time in total.
Colnago C64 - The Naked Build; Colnago C60 - PR99; Trek Koppenberg - Where Emonda and Domane Meet;
Unlinked Builds (searchable): Colnago C59 - 5 Years Later; Trek Emonda SL Campagnolo SR; Special Colnago EPQ

RyanH
Moderator
Posts: 1948
Joined: Tue Jan 17, 2012 4:01 pm
Location: Los Angeles, CA
Contact:

by RyanH

@calnago, thanks I'll look into MB. What's your recommended timeframe for a checkup on the items? Also, so if I pull the post and notice some corrosion, what do you recommend to clean it? For this time around I used CLP and a brush.

@kode54 This wasn't pretty but since my post has a hollow section through it where the yokes go through (it intersects the post), I took a 5mm long T handle allen key and used it for leverage to slowly rotate from side to side. Initially it didn't do anything but then it started to make a slight noise indicating it was budging ever so slightly. I kept at it for a good 15 minutes until I was able to move it about 1/16 of a rotation then I just went back and forth as I pulled up.
Strava
Current Stable. The Snob Machine
The Ex's. LS Siena: 6.21kg | Parlee Z5 SLi: 5.9kg | LS Xicon: 5.76kg | C59: 5.7kg | Cervelo R5ca: 5.09kg | Fuji Altamira SE - 6.2kg | Scott Foil - 6.2kg | Evo - 5.18kg | LS Classic - 6.7kg | The Crumpton - 5.9kg

kode54
Posts: 1184
Joined: Tue May 23, 2006 9:39 pm

by kode54

thx Ryan.

personally, the seat post is toast, so i would be willing to drill a hole through it closer to the frame for the best leverage to do what you did. its a good idea, since i really don't want to ruin the carbon fiber rails on my Fizik saddle.
- AX Lightness Vial EVO D + DA9150 + Enve SES 3.4 carbon hubs
- Parlee Altum + DA9150 + Enve SES 4.5 carbon hubs
- Parlee ESX + DA9150 + THM SRM PM + Enve SES 6.7 CK hubs
- Independent Fabrication Ti FLW + DA9100 + Enve 3.4 CK hubs

User avatar
Calnago
Posts: 6003
Joined: Sun Nov 07, 2010 9:14 pm

by Calnago

RyanH wrote:@calnago, thanks I'll look into MB. What's your recommended timeframe for a checkup on the items? Also, so if I pull the post and notice some corrosion, what do you recommend to clean it? For this time around I used CLP and a brush.

Ha, that really varies, just use your judgement. If you live in a really wet area and ride in the rain, obviously you should pay a little more attention to things. If you sweat a ton and it drips into your headset area, that's something I'd check a little more frequently. I just overhauled a TIME headset that was a mess from all the sweat that dripped into it. Like salt water. On the other hand, I've had neighborhood friends who never ride and have a perfectly good bike that's been sitting in the garage forever. They think they need a tuneup before they can ride it. I say "why, it's in the same condition as the day you bought it, just dust if off, put some air in the tires, and have fun.".
Something as simple as waterbottle cage bolts should at least be looked at now and then, because they are often put in dry and then all kinds of water and sports drink crap can get in there. But if you use grease or this stuff or low strength Loctite, it's all a very good preventative measure. It's amazing how long bike stuff can last that's taken care of. At least the non-consumables. And it's a good idea to look underneath your BB to see how messed up stuff is down there and whether a simple dousing of water with a brush might help clean out all the dried sugary sports drink that sometimes finds its way down there and gets your derailleur cables (mechanical) nice and sticky.
On brand new bikes, it's a good idea to strip everything and rebuild it, because they often have a lot of stuff just bolted on dry. And then you have peace of mind that everything is as it should be as well. Derailleurs especially, just screwed into the derailleur hanger never to be looked at until something is terribly wrong. I just worked on two brand new bikes where the rear derailleur was installed completely "dry" into the hanger. A little grease and it will be good for a very long time. Makes maintenance on your bike down the road so much easier and enjoyable. Nothing worse than going to make a little adjustment and the bolt is seized, rusted, or strips while you try to get it loose.
Colnago C64 - The Naked Build; Colnago C60 - PR99; Trek Koppenberg - Where Emonda and Domane Meet;
Unlinked Builds (searchable): Colnago C59 - 5 Years Later; Trek Emonda SL Campagnolo SR; Special Colnago EPQ

Post Reply
  • Similar Topics
    Replies
    Views
    Last post