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The Right Wing
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Good carbon post stuck in good Al frame. Both Pinarello. Only in there one year, but stuck real bad.

Does anyone know a way to put some tourque on the round part of the post, since any more on the top part where the seat goes will break it right off.
 

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chamois creme addict
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Frame as leverage

53T said:
Good carbon post stuck in good Al frame. Both Pinarello. Only in there one year, but stuck real bad.

Does anyone know a way to put some tourque on the round part of the post, since any more on the top part where the seat goes will break it right off.
I would first try putting on an old saddle that can be destroyed and clamp the saddle into a bench-mount vise. Then grab the frame by the head tube and rear stays and give it a twist.

If the seat clamp's bond breaks free from the post, then I would try clamping the post in the vise and repeating the above. Either way the seatpost is probably toast. FWIW, Thomson makes a Pinarello compatible size and you can install that sucker with lots of grease and likely avoid this problem in the future.
 

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Air Force
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I had the same problem with a Campy Record carbon post. I took it to a shop and they said the same thing as Eric_H. I tried it and the vise slipped and the pictures can say the rest. If you do get the post out without a problem make sure to use a grease that wont mess up the clear coat and carbon.

I wounder if I could cut the post below the crack and glue the mount back in?
 

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You can try dish detergent mixed with water for a slippery mix. Put enough in the water to make it very slippery. Glycerin bar soap is very slippery.
 

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This is the standard link for this

http://www.sheldonbrown.com/stuck-seatposts.html

In para. XIII, Sheldon recommends ammmonia to loosen an aluminum post. Even though you have a carbon post, this would still apply. Plastics reinforced with carbon fibers (your seatpost) can induce galvanic corrosion in an attached aluminum structure and produce aluminum oxide—the white, powdery substance between your post and the frame. In simplified theory, the ammonia attacks and eventually dissolves this aluminum oxide. In practice, I would think this would take lots of ammonia and a couple of days. Worth a try, anyway.
 

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Super Moderator
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keepitsimplespeed said:
wouldn't ammonia hurt the paint on the frame - and how do you get the ammonia into the seat tube?
The ammonia shouldn't hurt the paint, as long as you're not using the anhydrous stuff you use to cook meth with. Just dribble some down the post, like it was penetrating oil, and try to keep it away from lubricants.

Ideally, you could pull your BB, turn your frame upside down, and pour a bit more in, esp. if nothing happens via the other way.

Just because I hadn't seen it mentioned, but sometimes in desparate situations, tapping the seatpost IN a BIT can break the corrosion enough to get things started. Tapping on the post can also help the penetrant do its job.

Finally, never done this, but others had mentioned that the press-glued heads of posts often pop off long before one has had enough torque on them to free the post. Couldn't you drill holes through the shaft of the post, and fit a rod through, to give yourself some leverage?
 

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Frog Whisperer
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keepitsimplespeed said:
wouldn't ammonia hurt the paint on the frame - and how do you get the ammonia into the seat tube?

considering the frame and post are toast if you can't get it apart, who cares about the paint?


I would pour ammonia into the seat tube, cut the post if necessary, put a cork in or something to seal it then turn upside down to bring it back to the "top". Then heat the seat tube a bit with a hair drier, then posssibly "buzz" it a bit with a random orbital sander of some other form of vibrating device... (use your imagination)...trying to get capillary action to draw the ammonia into the micro spaces)...let it sit a few day if neccessary, if that doesn't work, try a heat gun (much hotter)......Like I say, screw the paint, talk to Dave or Chris about "rattle can" painting.... What have you got you lose?
 

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Frog Whisperer
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BTW the moral of this story is loosen and move the seat post once a month or so to make sure it doesn't seize.
 

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Removing the BB, plugging the seat tube, and pouring ammonia in there is a good idea. Hardware stores sell different size rubber plugs that expand by using a screw that goes through the middle that's attached to a washer on the other side.

Using a hair dryer is another good idea.

To prevent this from happening in the future, what about removing your carbon seat post and putting powdered graphite on the seat post? Powdered graphite is easily bought in hardware or automotive stores. It comes in a small jar. It is the only lubricant recommended for door locks as it isn't an oil such as oil or a wet lubricant as WD40 and won't attract dirt into the lock.
 

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The ammonia trick worked for me when my carbon post siezed in a Fondriest frame I have. I loosened the seatpost clamp and poured the ammonia around the base of the post where it met the frame and let it seep in. Did that for a couple of days. Then, I put an old saddle in the frame, attached that to a bench vice, used a heat gun to heat up the area around the clamp, and told my 22 year old son to twist away....... after a couple of trys it started to move and we extracted the post. Saddle will never the same but the frame and post were saved.
Now, its coated in grease and I loosen it every couple of weeks.
BTW, the owner of our LBS had a Campy carbon post sieze in his Griffen..... they ended up cutting it out in pieces with a Sawzall.......but it saved the frame.
 
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