Seat post stuck but how to increase saddle height?

Commuter42

My road bike has a carbon seat post in an alu frame, it's stuck in place and even the bike shop told me there's no hope if getting it out (it seems to have welded itself in there over time). I want to to increase my seat height just a wee bit, but the only idea I've had so far is to increase the padding in my shorts! Are there any road bike saddles on the market that have a depth characteristic, rather than the usual length/width dims given by the retailers? Or can I buy a seat post extender that can be fitted without having to remove the seat post from the frame? Or any other ideas?? Thanks

fenix

This has worked for Wappygixer in the past. I think its the best option for you.

Postby Wappygixer » Sun Jan 10, 2010 19:44 pm

I've removed a few stuck seat posts over the years.
One way in which I've never been beaten is to cut the post just above the collar.
Then with a hacksaw blade cut down the length of the post as it goes into the frame.
Its a long drawn out job but works.
You must keep the hacksaw blade level so as not to cut the frame.
Once you have cut through then start again in a different place so as to remove a length.
The remaining post will now almost fall out.
Good luck and keep at it, its very rewarding when it does go.

timothyw

Have you tried hot/perhaps boiling water poured over the seattube to expand the aluminium?

That's probably what I'd try, keep the bike assembled, remove the seatpost clamp to make absolutely sure, make sure there is a saddle fitted (ideally one you don't value that highly...) pour a kettle of hot perhaps not boiling water (depending on how you value the paintwork/decals) over the seattube over the area that the post is inserted, then stand the bike up, put a foot on one of the pedals to brace it and wiggle the saddle for all you're worth.

Might be worth giving the saddle a few encouraging digs with the rubber mallet to get it twisting.

If it twists, but won't come up, saturate the area where the seatclamp would be with gt85 and keep twisting to try and work the lube in.

If you get absolutely no joy with that (and similar) strategies, might be worth taking a hacksaw blade to the post, although you need to be very careful if doing so, as carbon fibre dust is most definitely not good for you - wear gloves and a facemask.

The Rookie

The usual issue with carbon posts in ally frames is aluminium oxidation, the powdery oxide builds up and jams the post in place.

This can be dissolved using ammonia household cleaner.
Wrap some kitchen roll around the post just above the frame and then use a wide tape wrapped around the frame and the kitchen roll to create a funnel.

Ammonia dissolves the Al Oxide, other liquids just expand it further!

Drizzle in the ammonia and allow to soak into the gap, keep doing so. After about 24 hours it will come free, sometimes its worth knocking it further in slightly (easier to apply the force) to loosen it before pulling it out.

This was how we got the sons 34.9mm diameter (lost of area gripping!) alloy post out of his Scott Carbon frame.

N0bodyOfTheGoat

Are there any holes on the frame, around the underside of the bottom bracket, where you could leave the bike upside down and pour some coke down the seat tube for a day or so?

Alternatively, get some coke into the frame via an allen bolt hole on the seat tube?

Then hit saddle with hammer, placing a block of wood between saddle top and hammer.

Worked with my stuck mid 1990s Peugeot 531 frame and a stuck post, no idea if this works with a carbon post in an alloy frame.

apriliarider

http://www.theseatpostman.com/

Couple my mates have used him with supposed "never get that out of there" jobs

Cheers

MW

darkhairedlord

Thermic Lance.
Easy to DIY one with a length of steel brake line, wire wool and a supply of oxygen.
works every time.

Matthewfalle

However, if he doesn't want to do all that and just wants to play with saddles naturally they will all vary in thickness (you look at a Selle Italia SLR as compared to a Turbo and you'll see what I mean) but also the height between the rails and the saddle itself - some racing saddles are really tight and close together (SLR) some have a big gap between the rails and the saddle.

Otherwise as above for removal.

Also try penetrating fluid (not WD or similar but Plus Gas etc), leave it to soak for a few days after repeated applications then put the seat post in a vice and use the frame as the lever - worked on an ali seat tube stuck in a carbon frame for me.

Brakeless

Ignore everything above.

Go and buy a new bike. (a really expensive one) It's much more fun and far less hassle.

Wheelocheese

apriliarider wrote:

http://www.theseatpostman.com/

Couple my mates have used him with supposed "never get that out of there" jobs

Cheers

MW

Seconded.