What grease for a carbon seatpin in an alloy frame
09-11-20, 11:13 AM
#1
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What grease for a carbon seatpin in an alloy frame
What type of grease should I use when using a carbon seat pin in an aluminum frame? In theory, they shouldn't bond together but I seem to recall reading that grease is needed, perhaps to help avoid creaks?
Last edited by Welshboy; 09-11-20 at 03:46 PM.
09-11-20, 12:11 PM
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None; do as jdocs suggested, unless you'd like to have "eternal slipping". If greased already, remove pin/post and clean with isopropyl (rubbing) alcohol until squeaky clean.
09-11-20, 02:08 PM
#4
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What Juan said above. CF seatposts ("pins") are apt to slip as it is with nothing on them...even when torqued properly. In my case I had to resort to using CF friction grip paste.
Dan
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09-12-20, 07:21 AM
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Before applying the assembly paste, I recommend a wrap or two of eg. masking tape, at and above the level you want to insert your seatpost. Inadvertently inserting your post a bit too far and then pulling it back out of the bike, can leave some good scuffing/scratching of your post from the assembly paste (especially noticeable if you have a high gloss finished CF post.
09-12-20, 10:19 AM
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I disagree. There is galvanic corrosion potential, so use grease, inspect periodically,
and use fibergrip if there is a slipping issue.
Quick google search:
"The issue with using carbon fiber materials for fastener applications is that carbon fiber is electrically conductive, thus making it more susceptible to galvanic corrosion. When coupled with a fastener, bolt or nut, the situation worsens. Aluminum and plain steel, when coupled with a carbon composite, are both highly susceptible to galvanic corrosion.
Galvanic corrosion with carbon fiber materials has been an issue for decades, but experts have yet to produce a universal solution for the problem."
and use fibergrip if there is a slipping issue.
Quick google search:
"The issue with using carbon fiber materials for fastener applications is that carbon fiber is electrically conductive, thus making it more susceptible to galvanic corrosion. When coupled with a fastener, bolt or nut, the situation worsens. Aluminum and plain steel, when coupled with a carbon composite, are both highly susceptible to galvanic corrosion.
Galvanic corrosion with carbon fiber materials has been an issue for decades, but experts have yet to produce a universal solution for the problem."
Last edited by woodcraft; 09-12-20 at 10:23 AM.
09-12-20, 11:55 AM
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& 7005 & 7075 aluminum alloys include a % of Zinc (dry cell batteries were alternating layers of C & Zn..)
09-12-20, 12:00 PM
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I disagree. There is galvanic corrosion potential, so use grease, inspect periodically,
and use fibergrip if there is a slipping issue.
Quick google search:
"The issue with using carbon fiber materials for fastener applications is that carbon fiber is electrically conductive, thus making it more susceptible to galvanic corrosion. When coupled with a fastener, bolt or nut, the situation worsens. Aluminum and plain steel, when coupled with a carbon composite, are both highly susceptible to galvanic corrosion.
Galvanic corrosion with carbon fiber materials has been an issue for decades, but experts have yet to produce a universal solution for the problem."
and use fibergrip if there is a slipping issue.
Quick google search:
"The issue with using carbon fiber materials for fastener applications is that carbon fiber is electrically conductive, thus making it more susceptible to galvanic corrosion. When coupled with a fastener, bolt or nut, the situation worsens. Aluminum and plain steel, when coupled with a carbon composite, are both highly susceptible to galvanic corrosion.
Galvanic corrosion with carbon fiber materials has been an issue for decades, but experts have yet to produce a universal solution for the problem."
