Seized Seatpost - Revisited

[npn]

Re:

I really don't know if it's worth it. The bike was low-mid end, but this is the last year (1999) that it was produced, and the frame is handmade in the US. The fork needs to be replaced which is the most expensive component (unless I need to paint the frame, add decals).

This is a photo of the 1999 Trek 930, tho not the one in my possession:

 

[Gruff]

Re:

If the seatpost isn't too far down or cut flush with the frame then you could try banging it down a fraction to break the bond, using a copper mallet or an ordinary hammer if you are going to replace the post.
Once the bond is broken you can try to twist it out slowly. Its also worth spraying liberally with "Plus Gas"

Good luck

 

[Gaddmeister]

Re: Re:

I really don't know if it's worth it. The bike was low-mid end, but this is the last year (1999) that it was produced, and the frame is handmade in the US. The fork needs to be replaced which is the most expensive component (unless I need to paint the frame, add decals).

This is a photo of the 1999 Trek 930, tho not the one in my possession:

I think it's worth it,where are you based?

 

[npn]

I'm in the US, in the Chicago area.

I bought the bike for $80 and if in excellent condition I can sell it $175. I'm not sure if I want to keep it as I'm not a fan of Treks but Marin is a totally different story. Here's my Marin project:

viewtopic.php?f=1&t=356050

 

[npn]

No difference after I soaked the tube upside-down in vinegar and lemon juice... I got PB Blaster and started soaking it with it. I've got all winter to do this...

 

[JoeG]

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

 

[The History Man]

Hmm CO2 cartridge was new to me. Will try this before getting the freeze can stuff.

 

[npn]

I've tried everything on Sheldon's list except the caustic soda.

 

[Gaddmeister]

Re:

Caustic soda is so fun!

 

[Twisty]

Get a can of freeze spray, if you are going to replace the seatpost then you can drill a small hole on the side of the seatpost and spray directly into it. If you want to try and keep the seatpost then best to take out the BB and spray in to the seatpost from there although you can blast the outside of the seattube instead but you will need to spray for longer.
The aluminium post will contract more than the frame so this should allow you to pull out the seatpost, standing on the saddle while you twist and pull on the frame works well.
There was a thread here just a few weeks ago with lots of details and a chart I put together with the temperature coefficients.
Caustic soda is fun but it will damage paint work and you should dismantle the whole bike otherwise the vapour travel around the frame and attack other alumimium parts on your bike.