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Discussion Starter · #1 ·
I'm going to be buying my first carbon seat post. It's going inside an al frame. What's the story, do I use a special carbon paste on the seat post so it doesn't freeze in or not?

Doesn't this paste soak into the carbon and then make it slippery?

Do you use this paste on carbon seat posts and carbon frame bikes or only al bikes?

What about carbon seat posts and Ti frme bikes?
 

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lawrence said:
I'm going to be buying my first carbon seat post. It's going inside an al frame. What's the story, do I use a special carbon paste on the seat post so it doesn't freeze in or not?

Doesn't this paste soak into the carbon and then make it slippery?

Do you use this paste on carbon seat posts and carbon frame bikes or only al bikes?

What about carbon seat posts and Ti frme bikes?
Frame/Post
Ti/Ti = Ti Prep

Ti/CF = Grease

Ti/Alum = Grease

Alum/Ti = Ti Prep or grease

Alum/Alum = grease

Alum/CF = grease

CF/CF = paste or grease

CF/Alum = grease

CF/Ti = grease
 

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Moderatus Puisne
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Hey, I don't know from PE, but Zinn et al have told me that you ought to never grease a CF post.

PS, OP -- "Soak into" the carbon fiber? That made me laugh. I've never heard o' that.
 

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Argentius said:
Hey, I don't know from PE, but Zinn et al have told me that you ought to never grease a CF post.

PS, OP -- "Soak into" the carbon fiber? That made me laugh. I've never heard o' that.
No Zinn did say grase is OK. He had guys from ZIPP and Bontrager explain this.
Regular bike grease will NOT ruin our CF post.

If you post slips, then don't use grease. I use a very light grease for years now with no issues or damage to any post.
 

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Discussion Starter · #5 ·
I've heard bike grease is bad and they make special carbon "grease" or paste for this purpose. Grease itself soaks in to the carbon, makes the seat post slip, and you can't get rid of it.
 

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Hrm. Lemma go geta my book... it's weird how there are 54 authorities on any subject, with different opinions!

--

Edit: Yep: "Do not grease carbon seatposts." and, also, "Carbon seatposts often slip down ... make sure there is no grease on the post. Grease [on carbon posts] is unnecessary, and is often damaging to the clear coat on the seatpost." From Zinn and the Art of Road Bike Maintenance.
 

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lawrence said:
I'm going to be buying my first carbon seat post. It's going inside an al frame. What's the story, do I use a special carbon paste on the seat post so it doesn't freeze in or not?

Doesn't this paste soak into the carbon and then make it slippery?

Do you use this paste on carbon seat posts and carbon frame bikes or only al bikes?

What about carbon seat posts and Ti frme bikes?

The paste (Tacx Dynamic Assembly paste, or Ritchey Liquid Torque, also FSA sells it with another name) is a gel-like substance with some micro polymer spheres suspended in it. The spheres are useful with a carbon seatpost in any frame: 1) They will make inserting the post easier because the post will "roll" on the spheres. 2) When tightened the spheres resist compression, exerting force against the seat tube and the seatpost. This helps to prevent slipping and reduces the amount of torque required on the seat clamp. 3) Having the spheres between the post and the frame will keep the post from becoming corroded and stuck.

The paste can also be used with any seatpost/seat tube combo, or on handlebar/stem interfaces and steerer tube/stem interfaces. Basically any clamping point where a torqure reduction is required. Ritchey and Tacx claim a 30% reduction in torque to have the same clamping force using this paste. The only downside is that it does not resist water penetration like grease, so using the paste will result in more water penetrating the seat tube in rainy weather.
 

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Maybe Zinn needs to learn more....

or read what someone is writing in his books!!

Argentius said:
Hrm. Lemma go geta my book... it's weird how there are 54 authorities on any subject, with different opinions!

--

Edit: Yep: "Do not grease carbon seatposts." and, also, "Carbon seatposts often slip down ... make sure there is no grease on the post. Grease [on carbon posts] is unnecessary, and is often damaging to the clear coat on the seatpost." From Zinn and the Art of Road Bike Maintenance.
Ok:

[SIZE=-1]The cosmetics of carbon
Dear Lennard,
I pulled the Giant brand OE carbon fiber seatpost (stock on OCR road and VT mountain bike models, among others) out of my Titanium Raleigh cyclo-cross frame with the intention of using it on a hard tail mountain bike. Unfortunately, the clear coat for the first two or so inches that were inside the seat tube (in what looks like an aluminum shim) is almost opaque, fading to merely cloudy by the bottom. I rode it on the mountain bike this weekend at near full extension and there were no scary cracks or pops, but wonder if its dangerous, or just ugly.
[/SIZE]
[SIZE=-1]Also, is there any way to prevent this discoloration on the new Alpha Q post that's replacing it?
Marc
[/SIZE]
[SIZE=-1]Dear Marc,
The discoloration is most likely just on the clear coat and does not affect the fibers and hence the strength of the post. Probably the galvanic corrosion reaction between the seatpost and the aluminum seat tube sleeve discolored the post. To prevent it from happening on your new post, at a minimum pull it out frequently and grease it (and if it slips use Tacx, Ritchey or FSA carbon assembly paste on it instead). I suppose you could also wrap it with something as was mentioned last week to shield it from the aluminum.
Lennard
_________________________________________________________________
[/SIZE][SIZE=-1]Dear Tom,
I have always greased my own carbon posts without any problems, blissfully ignorant, as I had never bothered to read the seatpost instruction manuals (dare I say that when I write maintenance manuals!?!?). I was deluged with mail about this subject after posting numerous manufacturers' responses saying not to grease carbon posts. Posted below are some horror stories of riders who, like you, followed the instructions and did not grease their posts. But immediately below, you will find a differing opinion on the subject of whether to grease a carbon seatpost from carbon guru Craig Calfee. In the end, you will have to decide for yourself what to do, since there is obviously no consensus on this.
Lennard

_________________________________________________________________

[/SIZE][SIZE=-1]From Craig Calfee [/SIZE]
[SIZE=-1]Dear Lennard,
Thankfully! An opportunity to dispel the myth that one shouldn't grease a carbon post!
[/SIZE][SIZE=-1]I don't know where the myth started, but carbon composites are not affected by grease. Our advice is simple: If the seatpost fits tight, grease it. If it slips, de-grease it. As has been known for many years, when aluminum and carbon fiber contact each other, galvanic corrosion can start. That is why Calfee uses a fiberglass sleeve as a seat tube shim. Aluminum seat tube (or sleeve) and a carbon post will result in corrosion of the frame and possible seizure of the post within the frame. A carbon sleeve on an aluminum post will result in corrosion of the post. Salty environments accelerate this corrosion. Anodizing merely slows it down. About the only common chemical that will hurt carbon fiber is paint remover (which attacks the resin between the fibers). But there are many solvents that will dull a nice paint job.
Craig Calfee
[/SIZE]
 

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So...

If it slips, then Carbon Paste.

No slip, grease!
 

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Well, see?

What's a guy like me to do with all'n this back'n and forth'n!

Either way, thanks for the toothpaste tip, seems to work fine...
 

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Hearing problems?

lawrence said:
I've heard bike grease is bad and they make special carbon "grease" or paste for this purpose. Grease itself soaks in to the carbon, makes the seat post slip, and you can't get rid of it.
That may be what you heard, but it is not true. CF is used for derailleurs, which are constantly exposed to oil and grease and this is not a problem. The grease will not penetrate the clear coat or soak into the CF, and that is not the reason the post slips. The post slips because it is slightly smaller than the seat tube/clamp/sleeve.
 

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Kerry Irons said:
The post slips because it is slightly smaller than the seat tube/clamp/sleeve.
Well several companies and Cerbon gurus also blame the shiny finish compared to a matte finish.

Either way, I ahve not had a CF post slip when used with a decent clamp. I had 2 WW clamps let a CF post slip a tad. Once I used the carbon paste, they never slipped agin.
 

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how do I apply the tacx/ritchey/fsa paste?

I have a carbon post in a carbon frame and also an aluminium post in my second carbon frame.

Question: How do I correctly apply the Tacx or Ritchey or FSA paste to both of my posts to prevent slipping and to reduce the clamping torque?

How much paste do I need to apply and how big a surface do I need to coat? Do I apply to inside of the seat tube or to the outside of carbon/alum post or perhaps apply paste to both surfaces?

Thank you in advance!
 

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acid_rider said:
I have a carbon post in a carbon frame and also an aluminium post in my second carbon frame.

Question: How do I correctly apply the Tacx or Ritchey or FSA paste to both of my posts to prevent slipping and to reduce the clamping torque?

How much paste do I need to apply and how big a surface do I need to coat? Do I apply to inside of the seat tube or to the outside of carbon/alum post or perhaps apply paste to both surfaces?

Thank you in advance!
You just need a thin coat. I put it on the post and nsert the post. Wipe off the excess and torque your clamp to the proper value.
 

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I have a Ti frame and a carbon seatpost. The Tacx paste works great...Before I started using the stuff any thing that involved removing a setpost from my frame was a huge ordeal. With the paste it is a breeze...
 

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Wow!

After reading these posts, I pulled my seatpost to check. It had not been pulled out since I purchased the bike 2 years ago, and the post was covered with a fine, white powder. Galvanic reaction to aluminum? I assume so. I wiped the powder off and the post looked like new. It is now greased!
 

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What is required to remove Liquid Torque after use, or would it ever be necessary, say in the case where one decides to change to a different stem after using it?
 
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