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Aluminium post stuck in a ti frame


Speeding Up
Jul 31, 2007
Well, it's come to this. After dousing everything in oil but the creak continuing, I took the bike to the lbs who took the bb out, tightened the cassette and checked the spokes. The reason for the creak is that the post is stuck in the frame.

After I had a bike fitting a couple of months ago, I forgot to reapply some of that non-bonding stuff so the post is now thoroughly wedged in and won't budge.

Does anyone have any suggestions for something that will loosen this? I have been spraying some Japanese silicon spray stuff on it every day and giving it a pull.

Sheldon Brown suggests ammonia for aluminium posts - anyone know how/where I could get this? That or WD-40 - but can you buy this in Japan? I haven't seen it anywhere.
There`s an equivalent to WD-40 here, it`s called C-56, in a spray can, red cap. It seems to be exactly the same as good old WD-40...
sorry to hear. I'd suggest 2 options:
1. C-56 (WD40) soak. Not just from top down, but I'd alternate days after taking bottom bracket off and dripping the lube and keeping frame upside down every other night.
2. If you don't mind sacrificing an old seat or your seatpost - put on an old/no longer used seat and give it your best "Incredible Hulk" torque treatment. Next move would be to attach the seatpost to a vise on a bench (or attache a long rod to seatpost), use the frame for leverage, and give it a go.
Hey Lee,
I had a similar issue with my steel seat-post being completely stuck in the steel frame of my touring bike. I spayed lube on it every day as you're doing and tried to twist it free, with no luck. I got the biggest spanner I could find from the home centre - tightening it around the top of the seat-post and used it for some of that serious "Incredible Hulk" torque treatment. After a further week of this abuse it finally came loose. It was fine to use again.

I've still got that spanner - far to big for any other use - so let me if know if you want to borrow it -

from leonard zinn. oh what is the seat post make and how about the frame?

This is a serious job; if you make a mistake, you run the risk of destroyingthe frame. If you're not 100 percent confident in your abilities, go tosomeone who is—or at least to someone who will take responsibility if theyscrew it up.
1. Remove the seat-lug binder bolt. Sounds easy enough.
2. Squirt penetrating oil around the seatpost and let it sitovernight. To get the most penetration, remove the bottom bracket, turnthe bike upside down, squirt the penetrating oil in from the bottom ofthe seat-tube, and let it sit overnight. Coca-Cola is also a good rust-busterand can often free a corroded-in seatpost.
3. The next day, stand over the bike and twist the saddle.
4. If step 3 does not free the seatpost, warm up the seat-lugarea with a hair dryer to expand it. Discharge the entire cartridge ofa CO2 inflator at the joint of the seatpost and the seat collar to freezeit and shrink it. (Alternatively, ice the exposed seatpost with a plasticbag filled with crushed ice.) Now try twisting as in step 3.
5. If step 4 does not free the seatpost, you will need to moveinto the difficult and risky part of this procedure.
(a) You will now sacrifice the seatpost. Remove the saddle andall of the clamps from the top of the seatpost. With the bike upside down,clamp the top of the seatpost into a large bench vise that is bolted toa very secure workbench.
(b) Congratulations, you have just ruined your seatpost. Don't ever ride it gain.
(c) Perform the heat/ice or CO2 trick from step 4. Grab theframe at both ends and carefully apply a twisting pressure. Be aware thatyou can easily apply enough force to bend or crack the frame, so be careful.If the seatpost finally releases, it often makes such a large "pop" thatyou will think that you have broken many things!
6. If that did not work, cut off the seatpost a few inches abovethe seat lug and clamp the top of it in a vise. Warm up the seat-lug areawith a hair dryer to expand it. Discharge the entire cartridge of a CO2inflator down inside the seatpost to freeze and shrink it. Now try twistingas in step 4.
7. If neither step 5 nor 6 works, you need to go to a machine shopand get the post reamed out of the seat-tube. But this only works if youhave a cylindrical seat-tube; a machinist cannot help with a seatpost thatis not cylindrical.

Thanks very much for all the feedback chaps.

It's a Thomson Masterpiece setback - a beautiful piece of work that I'm loathe to damage or hurt it in anyway. However, the clamp that holds the seat is reasonably square so if I take the seat off I might be able to use a big spanner or something and turn it like that.

I'll also keep at it with the lube and try some of the options here, including the liquid or coke from the bottom bracket end (I saw the LBS guy do this so know how it's done now...).

Thanks again, will keep you posted...

Oil of Wintergreen / Methyl Salicylate

Oil of Wintergreen / Methyl Salicylate is the best penetrating oil and it smells GREAT. But you spill the bottle and it will make your eyeballs bleed. A big bottle will last you the rest of your life, in pure form it is strong stuff. I have seen it kick loose a totally galled [ Basically welded together by torque.] stainless steel nut and bolt. Since you are having dissimilar metals and your frame is much harder than your post, you may lose the post but your frame will live.

As always I think Leonard has the best advise. Good on you Kiwi.

But ME ? I would get some Oi O Wintergreen and let it soak overnight or longer. Remove all the parts from the seat post and WACK it down with a big freakin hammer just to pop it loose then jerk it out with big vice grips.

I just LIKE wacking things with big freaking hammers BTW.
if it don't pop loose on the first wack or two desist and try something else.

I am not sure where you would get O O W in Japan. I work in the shipyard and in the past have just asked a outside machinist shop x 38 for some but with the current Haz Mat rules it's not just floating around in every flam locker anymore.


Don't think any oil will really help much as it sounds like galvanic corrosion. If it does work at all it will take weeks of complete soaking.

Ammonia solutions are used as a cleaning agent and 'can' be bought off the shelf, try saying 液体アンモニア溶液 (えきたいアンモニアようえき). Alternative alkalis include baking soda.

The aluminium alloy surface is now porous (pitting) and will allow the ammonia solution to 'dissolve a thin layer' letting a bit of brute force to shear the contact points when applying torque to the post. The common titanium alloy (Ti-3Al-2.5V) used for bicycle frames should be able to resist the low concentrations you'll be using.
Alternative alkalis include baking soda.

Hi Kei,

Many thanks for this suggestion.

With the application, I guess the baking soda would need to be soluble to get into the tube. Is there any liquid that would best perform this function?

Hi Kei,

Many thanks for this suggestion.

With the application, I guess the baking soda would need to be soluble to get into the tube. Is there any liquid that would best perform this function?


Failing to find any Chivas Regal 25 Year Old lying around then good old water will do.

As for concentration, it's also used as a detergent for cleaning oily surfaces e.g. frying pans so dissolve it in warm to hot water. Not particularly strong but use rubber gloves and make a highly concentrated solution. The soaking may only require a few hours to overnight, if not soak it longer and test regularly. Some Hulk force will still be necessary.
Good News!!

Almost a month to the day since I posted this thread, I'm rather, actually very, pleased to announce that today the post finally came free.

Daily applications of WD-40 (both from the top, and through the bottom from one of the cage bolt holes) and a tug and pull on the seat every night seem to have worked. As Steve mentioned, it gave a mighty crack when it did come loose and it's now covered in this white gunky stuff.

With the beast finally free, I'll give it a proper clean up and then a good coating of that non-bonding stuff.

Thanks all!

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