Seized seatpost - BAD

jamlala

Hi all

My metal (I think) seatpost has seized into my carbon bike frame and WILL NOT BUDGE!
I have tried:-
a) constant boiling water drenchings,
b) weeks of WD40 spraying hoping that it will gradually sink in
c) brute force
d) brute force
e) brute force!!

I have take it to my LBS and they can't fix it. Please does anyone have any clues?!!

cooldad

Clamp the seatpost in a large vise.

Use the frame as a giant lever.

jermas

You could try a shock / freeze release spray. The spray rapidly cools the metal causing it to shrink and (hopefully) breaks through the corrosion.

kingdav

I've not used him but heard mention before of theseatpostman

Fingerling

Had this on a planet x frame. In the end I cut the seat post down an inch from the collar then carefully sawed the seat post from inside in 2 places. This took around at hour for each cut then carefully peeled them inwards. 3 hours later seat post out snd no damage.

sungod

aluminium alloy/cf, probably galvanic corrosion, the corrosion product has greater volume that the original metal of the post, it jams solid

wd40 won't help, it'll just make it much harder to get anything in there that might dissolve the corrosion product, boiling water will expand the alloy, making it tighter

as above, try freezer spray inside the post, it might create enough differential contraction to loosen it, try twisting the post before it warms, otherwise careful but laborious cutting is what i'd try next

next time use anti-seize

svetty

Fingerling wrote:

Had this on a planet x frame. In the end I cut the seat post down an inch from the collar then carefully sawed the seat post from inside in 2 places. This took around at hour for each cut then carefully peeled them inwards. 3 hours later seat post out snd no damage.

This. You just have to hope that the corrosion doesn't extend too far down the post. Careful use of a sharp hacksaw blade and you should be OK

N0bodyOfTheGoat

Can of coke into the seat tube while bike is upside down, leave for a day, put bike right way up and use rubber mallet to knock post into tube to free it.

Certainly works for alloy frames and posts, did it myself ~20 years ago, not tried with carbon frame.

Monty Dog

Coke contains a mild phosphoric acid which is great for removing rust. The galvanic corrosion which creates aluminium oxide and is jammng your seatpost requires a strong alkali to dissolve it. By all means empty a can of Coke down your seattube but you'll probably only make it stickier. Try something like ACF-50 instead.

g00se

my old LBS used this and it worked just as described:

https://www.effettomariposa.eu/en/products/carbomove/

http://road.cc/content/review/59182-effetto-carbo-move

apriliarider

Another for the Seatpostman - east, quick, cheap and no damage

shaw8670

I found sawing impossible. I cut it off 2cm above the collar and used a big rough round file and filed it thin. I had more control and could do it evenly. I filed in 3 places until they got thin , then started folding it inwards with pliers and more filing and tapping to break loose.

davidof

I used a corrosion dissolving product which I left in for days then a long lever. That was after trying everything else (vice etc). The seatpost was really really stuck. See video:-

https://youtu.be/Bfb6Ejb7pS4

It is hard to get the leverage on a post.