# Seat post slipping on carbon frame



## bmmonahan (Jul 9, 2007)

I finally have my Specialized Roubaix pro frame built up. 

One issue I am having is with my seat post. I put carbon prep on the seat post, tighten it using a torque wrench to Specializes' specs, after 30 to 40 minutes of riding the seat post will drop about an inch. 

Any suggestions on how to get the seat post to stay at the height I set it to?

Thanks.


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## Puchnuts (Oct 9, 2008)

On my brief experimentation with a carbon seatpost, I had the same problem. Not wanting to torque it down past the specs (and end up needing a proctologist) - I solved it by doing this: Remove carbon seatpost. Insert, with grease, an alloy Thomson seatpost. Never looked back.


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## Paul1PA (Sep 16, 2006)

Yep, I also had the Slippin' Seatpost Blues and it's very annoying. I then discovered this nifty Lock Ring made by Chase and readily available on eBay:

http://www.chasebicycleproducts.com/

This is a minimalistic clamp that mounts directly onto your seatpost (comes in 27.2 or 31.6mm sizes). Only weighs ~6 grams and immediately solved my slipping issues. 

Oh yeah, this Lock Ring has two other advantages: For one, it serves as a handy height index when removing my seatpost for travel or maintenance. And second, I actually feel more secure knowing such a critical component is held in place with two bolts instead of just one.

Below is a pic of the 27.2 size mounted on my LeMond Poprad (it's the tiny black clamp mounted directly above the OEM chrome seat collar).

Hope this helps! :thumbsup:

-Paul


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## andyk (Feb 17, 2009)

I had the exact same problem on my Roubaix Expert with Carbon Post.

Would slip about 3-4 inches during a shortish ride. Completely scuffed the seatpost too!

My LBS replaced the post Free of Charge and used some Carbon Assembly Paste. Once it was all torqued up again, I haven't had a single slip.

I think the stuff they used was Made by Tacx, or Finish line, but it did the job a treat


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## MattSoutherden (Jun 24, 2009)

Something like Pace RC005 Carbon Composite Shield Paste should help.


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## bmmonahan (Jul 9, 2007)

Thanks for the suggestions. This gives me some ideas to try.


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## albert owen (Jul 7, 2008)

Carbon paste or this accidental fix I discovered on my Pinarello.
Because of the odd sizing of Pinarellos, I bought a USE Shim to use with my Thomson Elite 27.2 post.
No grease or paste needed as the shim has a lip and absolutley NO marks on the post. Bingo!
Down size your post and get a shim.


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## High Gear (Mar 9, 2002)

Your post may be undersize. I would go back to the shop with it.


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## cyclust (Sep 8, 2004)

I had a Roubaix Pro a few years ago with the same problem. I lightly misted a bit of spray contact adhesive on the post, then let it dry for a day or two. This gave the post a slightly tacky surface. I've also heard that hairspray works great too.


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## OldSkoolFatGuy (Sep 6, 2007)

Toothpaste... Or use the carbon lube goo with a little bit of baking soda.... It just needs a little bit of a bite...

YMMV


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## canamdad (Jun 19, 2005)

I've successfully used Permatex Hylomar HPF gasket dressing to remedy slipping seatposts both carbon and alloy. Available in most any automotive supply store.


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## olr1 (Apr 2, 2005)

+1 for Hylomar, it was recommended to me by Trek USA, and works well to keep water out of the seat-tube too.


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## 01Forester (Apr 4, 2007)

I use the Finish Line Fiber Grip and it solved my problem.

http://www.finishlineusa.com/products/fiber_grip.htm


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## Mel Erickson (Feb 3, 2004)

cyclust said:


> I had a Roubaix Pro a few years ago with the same problem. I lightly misted a bit of spray contact adhesive on the post, then let it dry for a day or two. This gave the post a slightly tacky surface. I've also heard that hairspray works great too.


Hairspray is what many mountain bikers use on their grips to keep them from slipping and rotating. Spray it on the inside of the grip and/or handlebar and slip the grip on right away. This actually works initially as a lubricant to allow the grip to slip on easier but when the hairspray dries it's a mild adhesive. The key is using the really cheap hairpspray (like white rain) because it's got more alcohol and is stickier. One worry with a seatpost would be that it holds too good and makes the post difficult to remove.


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## WadePatton (Dec 29, 2006)

carbon assembly paste and a torque wrench. carbon is unforgiving.

the assembly paste works great for slippy aluminum/steel seatpost interfaces as well. i know.

lbs usually has partially used "sample size" containers that you may talk them out of. very few stock the stuff for sale. i bought some online...but a little dab will do it.

mind your torque.


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