Home

I am told by my LBS that the carbon seat post is stuck.
Any ideas to get it out?

12 comments

Avatar
mikeh126 [3 posts] 4 years ago
0 likes

A friend of mine operates a service to remove seatposts like yours.
Once seized, it is very difficult to remove them without damaging the frame.
He specializes in damage free seatpost removal, and can be contacted in Chorley, Lancashire by accessing his website: The Seatpost Man

http://www.theseatpostman.com/home

Good luck!

Mike

Avatar
Matt eaton [741 posts] 4 years ago
0 likes
Avatar
johndprobert [3 posts] 4 years ago
0 likes

This trick worked for me - turn the bike upside down, take off the cranks and pour a bottle of coke up the seat tube and leave overnight. Remember to be outside when you turn the bike the right way up...

Avatar
racingcondor [238 posts] 4 years ago
0 likes

Isn't the come trick for separating metals (acid vs corrosion)?

I'd be trusting the bike to Condor as my trustworthy LBS (they've rescued me from stuck barrel adjusters before). Hops you have a good option.

Avatar
richardh [59 posts] 4 years ago
0 likes

I hope you meant "coke trick"...

Avatar
mrkeith119 [87 posts] 4 years ago
0 likes

Have you tried pouring a kettle of boiling water over your frame, metal should expand more than carbon and help to release it.

Avatar
monty dog [463 posts] 4 years ago
0 likes

It's likely to be galvanic corrosion between the carbon post and the bare, aluminium sleeve inside the seattube. Aluminium oxide build-up jams the post in place and the likes of PlusGas etc will have little effect. Try some ACF50 which chemically breaks down the al-ox.

Avatar
earbyphil [10 posts] 4 years ago
0 likes

Many thanks for your suggestions. I should have pointed out it is a carbon seatpost AND a carbon frame.
Any further ideas?

Avatar
fukawitribe [1990 posts] 4 years ago
0 likes
earbyphil wrote:

Many thanks for your suggestions. I should have pointed out it is a carbon seatpost AND a carbon frame.
Any further ideas?

Have you tried compressing the seat stem, like the carbon specific recipe in the Sheldon Brown article Matt eaton pointed at ?

http://sheldonbrown.com/stuck-seatposts.html#carbon

That would seem to have a lot of sensible physics behind it - i'd also be tempted to try and rotate the seat post just after compressing to try and break any static bond.

Avatar
usedtobefaster [206 posts] 4 years ago
0 likes

I had the problem recently of a seized carbon seat post in a carbon frame, it took about 2 hours of rotating and pulling on the saddle to free the thing whilst trying to feed lube into the interface via the top of the seat tube. The whole area gets quite warm and all the time is was concerned about sheering the seat clamp off the post, but luckily it didn't happen.

Good luck with your removal.

Avatar
earbyphil [10 posts] 4 years ago
0 likes

Fukawitribe.
I am at work today so I will try the "push the seatpost down first" trick when I get home.

Usedtobefaster.
I'm a bit concerned what effect the "lube" will have on the carbon material as for some reason I understood I shouldn't grease or lubricate a carbon seatpost.

So, this promotes a general question;
Should one "grease" a carbon seatpost at all ?

Avatar
hampstead_bandit [614 posts] 4 years ago
0 likes
earbyphil wrote:

Fukawitribe.
So, this promotes a general question;
Should one "grease" a carbon seatpost at all ?

No grease should be used anywhere near a carbon frame (whether for seatpost or fork installation), if left it can easily cause the carbon fibre to swell as the oil in the grease gets absorbed into the CF

in the workshop, we always use a carbon paste like "Finish Line Fibre Grip" when installing carbon posts to carbon frames, carbon posts to aluminium/steel frames or an aluminium post to a carbon frame. For an aluminium post going into an aluminium or steel frame it would be Shimano anti-seize, never grease. Grease is for bearings...

for the headset bearings on a CF frame, if the bearing seats in the head tube are carbon, the bearings go in dry (seats degreased first with iso alcohol).

However, the bearing seat on the fork crown usually has an aluminium sleeve and this gets a smear of Shimano anti-seize, as does the top bearing face where the aluminium compression ring sits under the top cap. This prevents annoying creaking noises and also helps with water ingress over time