Road Cycling - Greasing a carbon seatpost

Hi there,

I have a Specialized S-Works road bike (aluminium frame) and have recently put a carbon seatpost on it without removing any residual grease from inside the frame. A friend of mine told me that if any grease gets on the seatpost then over time it could degrade the carbon composite and therefore there's a risk that the seatpost will become brittle and snap.

Anyone else heard about this?

Thanks for reading this and looking forward to your input.

Cheers

yes, i have heard of this. if the post hasn't been in long, take it out, and de-grease the pants off it, and the inside of your frame.

What is the purpose of greasing the seat post? Won't that just make the post slide up and down while you're riding?

What is the purpose of greasing the seat post? Won't that just make the post slide up and down while you're riding?

noise, and adjustment

cos I used to have an aluminium seatpost in an allu frame - there's a risk of chemical reaction which can chemical weld the post to frame.

Just forgot to remove the white anti seize before installing new post. Have now removed post which is only two weeks old and inserted rag using screwdriver and got rid of the vast majority of grease and removed most of the grease residue off the seatpost. There was some I could get off but just a couple of tiny patches.

Thanks for the input so far.

cos I used to have an aluminium seatpost in an allu frame - there's a risk of chemical reaction which can chemical weld the post to frame.


The problem lies in steel and aluminium parts contacting each other. Don't grease a carbon post - it shouldn't be necessary. Grease attracts crap, therefore, avoid it when able.

Hi there,

I have a Specialized S-Works road bike (aluminium frame) and have recently put a carbon seatpost on it without removing any residual grease from inside the frame. A friend of mine told me that if any grease gets on the seatpost then over time it could degrade the carbon composite and therefore there's a risk that the seatpost will become brittle and snap.

Anyone else heard about this?

Thanks for reading this and looking forward to your input.

Cheers That's bull. The reason is grease makes it too slickery and the binder bolt has to be overtightened with probable damage.

noise, and adjustment
Not really. But obviously,it it gets stuck coz of lack of lube,you cannot adjust it.

The problem lies in steel and aluminium parts contacting each other. Or most other dissimilar combinations. Two metals plus some moisture makes a battery. The resulting movement of metal atoms creates corrosion and slowly fuses the two parts together.

Of course, steel on steel will just rust solid. There's nothing like working on a old department store bike (about the only place you see steel posts nowadays)...

Various external thermal and stress factors may lead to the breakdown of CF. High temps, maybe over 1200 F, extreme flexing, high load stress, leading to material fatigue, constant contact with silicon carbide. Certain, and only certain types of petroleum based products may, may permeate the coating on the CF piece, but grease cannot breakdown CF.

I've never heard that about carbon fiber seat posts but it shouldn't cause any harm to wipe the grease off. On my first serious road bike (Vitus/105), I made the mistake of not greasing the aluminum stem. During a long group ride I heard this horrible creaking. After I got home I tried to remove the stem but is was frozen solid. Even after flipping the bike upside down and soaking in penetrating oil it still wouldn't budge. Eventually I sold the bike informing the new owner of the problem.

it might be counter-intutitive - but a lubed seatpost can be held more securely than one isn't lube and also can prevent seizing up.

Carbon should ALWAYS be dry.
alloy posts need grease or ti-prep in a, you guessed it, ti frame.

i don't think that grease will affect the CF - modern gasoline, fuel oil, diesel, etc. bulk storage tanks are constructed of fiberglass

is that what you guys are calling it these days....greasing the carbon seatpost?

grease will not dissolve a carbon seatpost or compromise its strucutre in any way, but it will make it slip.

is that what you guys are calling it these days....greasing the carbon seatpost?



HA!!!

actually - not all composite materials are the same.

Inside a bike frame made out of carbon composites - there is generally a layer of fibre glass in the seat tube to prevent corrosion from dissimilar corrison.

Most manufacturers tell you NOT to use grease - so I would just not to because they know better than us. Hairspray does wonders to keep the post in place. Don't use grease.