# Lube for carbon seatpost ?



## Steelguy (Apr 25, 2010)

When installing a carbon seatpost in a carbon frame, what do you use to prevent the seatpost slipping or seizing? Assembly lube? Hairspray?


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## Kontact (Apr 1, 2011)

Carbon assembly paste.

There's some newer formulations that don't have the plastic grit in it, but they all work.

Not lubing the post is a bad idea.


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## Special Eyes (Feb 2, 2011)

Carbon assembly paste is not a lube. You never lube a seatpost.


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## FBinNY (Jan 24, 2009)

Special Eyes said:


> Carbon assembly paste is not a lube. You never lube a seatpost.


*+1*
You don't lube things you're trying to *prevent* them from slipping. 

Greasing seatposts started with the advent of non-anodized aluminum posts used in steel frames. The grease isn't there as a lube, but to prevent corrosion.

Carbon posts are already pretty slippery, so greasing can make them hard to clamp. Dry assembly isn't OK because of corrosion, so a non-slippery anti corrosive is needed, aka carbon assembly paste.


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## Kontact (Apr 1, 2011)

FBinNY said:


> *+1*
> You don't lube things you're trying to *prevent* them from slipping.
> 
> Greasing seatposts started with the advent of non-anodized aluminum posts used in steel frames. The grease isn't there as a lube, but to prevent corrosion.
> ...


Park Tool lists assembly paste under "Cleaning and Lube". I don't think Jesus will cry when people use the term to describe applying goop between two parts to make sure they can slip apart when needed. Especially since there isn't a more succinct general term for this procedure, and all the companies that make anti-seize also call it a lube.

The point of grease, anti-seize AND assembly paste is to provide a non-permanent corrosion barrier and lubricant between slip fit and threaded parts. Assembly paste is simply a grease with a traction compound in it to allow it to hold under pressure, but slide otherwise. 

Compounds for holding things together are called adhesives. Seat posts are clamped, not glued.


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## bikerjohn64 (Feb 9, 2012)

Steelguy said:


> When installing a carbon seatpost in a carbon frame, what do you use to prevent the seatpost slipping or seizing? Assembly lube? Hairspray?


Finish Line makes a product for carbon assembly. Like the other posters have noted; it is a paste and has what feels like grit in the paste. The grit is actually small compressible particles that deform when components are tightened together. Apply an even coat around the post's base before insertion and alway use a torque wrench to tighten carbon components to manufacture's specs. If it keeps slipping down; then there's something else going on that needs to be checked out.


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## FBinNY (Jan 24, 2009)

Kontact said:


> Park Tool lists assembly paste under "Cleaning and Lube". I don't think Jesus will cry when people use the term to describe applying goop between two parts to make sure they can slip apart when needed. Especially since there isn't a more succinct general term for this procedure, and all the companies that make anti-seize also call it a lube.
> 
> The point of grease, anti-seize AND assembly paste is to provide a non-permanent corrosion barrier and lubricant between slip fit and threaded parts. Assembly paste is simply a grease with a traction compound in it to allow it to hold under pressure, but slide otherwise.
> 
> Compounds for holding things together are called adhesives. Seat posts are clamped, not glued.


Since one of the purposes of carbon assembly paste besides anti-corrosion is specifically to *increase *, *not reduce* the coefficient of friction, I prefer not to call it a lubricant, but you're free to call it whatever you want.


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## Kontact (Apr 1, 2011)

FBinNY said:


> Since one of the purposes of carbon assembly paste besides anti-corrosion is specifically to *increase *, *not reduce* the coefficient of friction, I prefer not to call it a lubricant, but you're free to call it whatever you want.


We don't use it to increase friction - dry posts clamp just fine. It is a grease with an additive that prevents slipping under clamping force, but it is still a type of lubricating grease.


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## FBinNY (Jan 24, 2009)

Kontact said:


> - .... It is a grease with an *additive that prevents slipping* under clamping force, but it is *still a type of lubricating* grease.


couldn't have said it better myself. 1984 is long past, things specifically made to *prevent slipping* are, by definition, not lubricants, but as I said earlier you're free to call them whatever you prefer.


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## Kontact (Apr 1, 2011)

FBinNY said:


> couldn't have said it better myself. 1984 is long past, things specifically made to *prevent slipping* are, by definition, not lubricants, but as I said earlier you're free to call them whatever you prefer.


Well, if you're going to correct the OP for using the term, why am I free to call them what I like?

I wouldn't have bothered posting at all if the immediate response to his question wasn't two people correcting his word choice - a choice the people who make the stuff encourage.


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## FBinNY (Jan 24, 2009)

Kontact said:


> Well, if you're going to correct the OP for using the term, why am I free to call them what I like?


The OP is also free to call anything by whatever name he wishes. I'm not invested in what others do.

I posted my initial +1 response not to correct language, terminology or semantics but to inform the OP that lubrication was counter productive to holding a post in the frame, and that the reason for grease or other products was as a corrosion barrier not as a lubricant.

The OP posted looking for help, and I tried to offer it as best I could. You OTOH posted just looking for a debate, and neither need not want my advice so I don't bother.

I don't know what others think but I post here and offer help for free, and am confident that it's worth every penny readers pay for it. That said, this is a public forum in a free (somewhat, but let's not go there) country, and readers of my posts are absolutely free to do or think whatever they want as far as I'm concerned.


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## Kontact (Apr 1, 2011)

FBinNY said:


> The OP is also free to call anything by whatever name he wishes. I'm not invested in what others do.
> 
> I posted my initial +1 response not to correct language, terminology or semantics but to inform the OP that lubrication was counter productive to holding a post in the frame, and that the reason for grease or other products was as a corrosion barrier not as a lubricant.
> 
> ...


Actually, I'm not looking for a debate - and I'm sorry if our back and forth lately makes it look like that.

In this case, I don't think anyone needed to be corrected - lube is a general term. I had already posted the correct "lube" or "stuff", so the two follow on posts to correct a perceived (but not necessarily correct) terminology problem seemed a little out of place.

As I pointed out, the people who make various gunks for preventing seizure of parts call their products lubricant, and the definition of lubricant is open enough to leave room for many substances that provide protection from corrosion or seizing. 

When there is a doubt about the definition of a word, I think it is more polite to assume the more inclusive version, especially if there is not a better word choice.

Anyway, I think you contribute wonderfully to the forum and am glad you're here. Hopefully you often feel the same about my contributions, because there just aren't that many pros who post here. Sorry if this stopped being collegiate.


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## FBinNY (Jan 24, 2009)

Kontact said:


> Actually, I'm not looking for a debate - and I'm sorry if our back and forth lately makes it look like that.
> 
> 
> Sorry if this stopped being collegiate.


No problem, I also didn't like where we were headed. If you read through the thread, you'll see that my post wasn't about terminology, but about why we put stuff - grease, paste or whatever people call it - on seatposts.

As for being collegiate that's not an issue, I don't have a solid link between respect and agreement. There's a world of room for different opinions on many issues and I have no problem respecting folks I may disagree with.


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## Special Eyes (Feb 2, 2011)

I never knew carbon fiber corrodes.


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## FBinNY (Jan 24, 2009)

Special Eyes said:


> I never knew carbon fiber corrodes.


I'm not sure it does. But think back to grade school experiments. Remember building a simple battery with Carbon and Zinc? 

Carbon in contact with various metals sets up the possibilty of Galvanic corrosion. In my experience, the aluminum seems to get the worst of the bargain, so it might be that you're saving that component more than the carbon one, but I can't confirm whether or not the carbon structure also suffers or not.

Either way, you need to protect carbon and aluminum from each other.


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## PoorCyclist (Oct 14, 2010)

Can carbon on carbon corrode?
The clamp is aluminum but it is on the outside of a slotted carbon tube.


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## FBinNY (Jan 24, 2009)

PoorCyclist said:


> Can carbon on carbon corrode?
> The clamp is aluminum but it is on the outside of a slotted carbon tube.


Don't know, but I use barrier agents almost every time I assemble things. one of the benefits of assembly paste (or as I call it, "traction compound") is it greatly lowers the clamping force needed to keep the post from slipping. This is a good thing because it lowers stress.

Another benefit is for riding in wet weather. Rear wheels throw water up at the top of the seat tube, where any tiny gap in the posts fit can allow it to wick in. A paste film improves the seal, acting as gap filler and helps keep water from weeping in and running down to the BB (sump).

I use grease on all my seatposts (no carbon, frame or post) and go one extra step by using silicone caulk to seal the slot. The frame also has a weep hole (drain) at the bottom of the BB, so it's sort of a belt and suspenders approach.


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## PoorCyclist (Oct 14, 2010)

I only use the carbon paste when it slips, it would scratch up the seatpost if you adjust the length a bit.
The bike I bought did not come with any grease but more more like machine oil on the seatpost.
I tightned 1nm less than written and it never slipped (there are 2 bolts though)


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## Kontact (Apr 1, 2011)

Special Eyes said:


> I never knew carbon fiber corrodes.


Any time you clamp two things together with a considerable amount of surface area you can end up seizing something. It doesn't take corrosion, just foreign substances. Sports drink and sweat can both really do a number on steerer tubes and seat posts.


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## sadisticnoob (Dec 6, 2009)

i have used FSA compounds and Finish line carbon grease works equally well


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## velocanman (Jul 15, 2011)

I got some carbon friction paste from the bike shop to reduce slippage of the carbon seat post in a steel hardtail MTB frame. I'm a big guy and it didn't really help so I put on a secondary clamp.

The paste sounds like a good idea. I've seen carbon posts nearly fused into a seat tube when not adjusted for a couple years. But that's my friend that doesn't maintain his equipment. The same guy I have to remind to change his chain..


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## Tende (May 11, 2003)

Well that's my question. Is it a good idea to use the compound when using a carbon post in a steel frame - I've got no slippage issues.


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