stuck seatpost

sroche21 said:

Hi all,

I want to change the position of my saddle but when I opened the bolt
behind the seatpost, the saddle stem remained lodged. I have tried a
little force, but not too much as it is a carbon frame and the last
thing I want is to damage that. I have added an oil spray which normaly
is good at unlocking stuff. But many tries later and my saddle remains
as was.

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

This is a fairly good list of suggestions.

Quoted message said:

Any suggestions, or is the best thing to bring the bike to a bike
shop?

I'd suggest trying a few of the suggestions from Sheldon's list. But,
it that doesn't work, I'd suggest taking it to the shop.

As a last resort they can always try cutting the seatpost out of the
frame.

--
Dane Buson - [email hidden]
The race is not always to the swift, nor the battle to the strong, but
that's the way to bet.
-- Damon Runyon

"sroche21" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Hi all,

I want to change the position of my saddle but when I opened the bolt
behind the seatpost, the saddle stem remained lodged. I have tried a
little force, but not too much as it is a carbon frame and the last
thing I want is to damage that. I have added an oil spray which normaly
is good at unlocking stuff. But many tries later and my saddle remains
as was.

Any suggestions, or is the best thing to bring the bike to a bike
shop?

Sean

--
sroche21

Could you try somehow heating the frame without melting the carbon. Or
freeze the carbon with gel pack to see if it shrinks enough.

sroche21 said:

Hi all,

I want to change the position of my saddle but when I opened the bolt
behind the seatpost, the saddle stem remained lodged. I have tried a
little force, but not too much as it is a carbon frame and the last
thing I want is to damage that. I have added an oil spray which normaly
is good at unlocking stuff. But many tries later and my saddle remains
as was.

Any suggestions, or is the best thing to bring the bike to a bike
shop?

Sean

Take a piece of 2 by 4 wood and place it on top of the stem after
removing the seat, and draw a line where the post meets the bike.
Place the 2x4 on top of the stem and hit it with a hammer. Once the line
goes down into the bike you know you have loosened it. Then you can try
to pull it out. As an almost last resort you could put a pipe wrench on
the top of the tube (not the seat mount part) and try to turn it while
pulling up. If that doesn't free it, then you are probably going to have
to go to the bike shop and let them work their magic, which may mean
drilling out the seat post. Some of them are nasty tight, just a fact of
life.
Bill Baka

sroche21 said:

I want to change the position of my saddle but when I opened the bolt
behind the seatpost, the saddle stem remained lodged. I have tried a
little force, but not too much as it is a carbon frame and the last
thing I want is to damage that. I have added an oil spray which normaly
is good at unlocking stuff. But many tries later and my saddle remains
as was.

Any suggestions, or is the best thing to bring the bike to a bike
shop?

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

--

John ([email hidden])

Dane Buson said:

As a last resort they can always try cutting the seatpost out of the
frame.

That works OK for steel frames, since the drill/saw blade will do more
damage to the seatpost than the frame. For carbon, the situation is
reversed. Be very careful if going with this option.

I presume the post is aluminum. If so, it has corroded, and aluminum
salts/oxides take up more room than the original aluminum. You might
manage to work it free with violence (banging it further in is better
than rotating, since the latter might damage the frame.

--

David L. Johnson

Arguing with an engineer is like mud wrestling with a pig...
You soon find out the pig likes it!

nash said:

Could you try somehow heating the frame without melting the carbon.

Very bad idea.

--

David L. Johnson

Arguing with an engineer is like mud wrestling with a pig...
You soon find out the pig likes it!

David L. Johnson said:

Dane Buson said:

As a last resort they can always try cutting the seatpost out of the
frame.

That works OK for steel frames, since the drill/saw blade will do more
damage to the seatpost than the frame. For carbon, the situation is
reversed. Be very careful if going with this option.

I presume the post is aluminum. If so, it has corroded, and aluminum
salts/oxides take up more room than the original aluminum. You might
manage to work it free with violence (banging it further in is better
than rotating, since the latter might damage the frame.

That was my idea with the piece of wood. Once you move it, even further
down, you know it is movable and not frozen in place. At that point you
could either clamp a seat on and try to rotate and pull or use a pipe
wrench, depending on how much you want to keep the seat post.
For the heat up the frame idea, not a good idea since the seat post
might expand even more and crack the frame.
Bill Baka

"Bill" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

David L. Johnson said:

Dane Buson said:

As a last resort they can always try cutting the seatpost out of the
frame.

That works OK for steel frames, since the drill/saw blade will do more
damage to the seatpost than the frame. For carbon, the situation is
reversed. Be very careful if going with this option.

I presume the post is aluminum. If so, it has corroded, and aluminum
salts/oxides take up more room than the original aluminum. You might
manage to work it free with violence (banging it further in is better
than rotating, since the latter might damage the frame.

That was my idea with the piece of wood. Once you move it, even further
down, you know it is movable and not frozen in place. At that point you
could either clamp a seat on and try to rotate and pull or use a pipe
wrench, depending on how much you want to keep the seat post.
For the heat up the frame idea, not a good idea since the seat post might
expand even more and crack the frame.
Bill Baka

So what does carbon do when heated just to be clear here?
the freezing works best with aluminum seat posts. OP has carbon

nash said:

"Bill" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

That was my idea with the piece of wood. Once you move it, even further
down, you know it is movable and not frozen in place. At that point you
could either clamp a seat on and try to rotate and pull or use a pipe
wrench, depending on how much you want to keep the seat post.
For the heat up the frame idea, not a good idea since the seat post might
expand even more and crack the frame.
Bill Baka

So what does carbon do when heated just to be clear here?
the freezing works best with aluminum seat posts. OP has carbon

I'm betting carbon has less expansion with heat than aluminum.
Water is the only thing I know of that expands at about 2C, and rubber,
as far as I know shrinks when hot.
Carbon fiber???
Don't know.
Bill Baka