Removing stuck or seized seatpost?

What material is the frame?

If t
Frame is steel and post is alloy then wrong or no grease. Water has got it and caused corrosion. Ally and steel corrode then expand.

I really thought I'd beaten this seatpost.

When I wedge the post in the storm drain on the road and twist the frame (don't have a vice) it now turns.

I really thought that when 'I broke the seal' I would be on the home straight, but I still can't remove the post from the frame-set. Tried belting it upwards with a heavy hammer using the clamp area. I'm getting a solid contact but it just won't budge.

@lynx it's a steel frameset, alloy post.

the only way is to wind it out while pulling. whacking it with a hammer won't work.

A vice and a heavy bench will really help. You need to encourage the frame away from the seatpost, rather than just twisting. Seatpost in vice, shoulder inside the frame, twist and stand up

PDry ice works. Especially as some people get food delivered in dry ice. Ally contracts more than steel when cold.

This in spades.

The nuclear option can be to drill a bolt through the post and attach it with chain to something sturdy, twist and pull. You can put your whole bodyweight behind it.

This is how Simon @ Norfolk Cycles does it.
https://youtube.com/shorts/8YO9v9oSHoM
There’s more to it than that, but…
(Don’t mine)

I have a seized seat post in an old steal frame .
How do i get it loose please and thanks ?

Show pictures of it here first if you can.
There are multiple methods possible: heat, lubrication, brute-force, cutting the post etc.

there are some good tips on this thread -
https://www.lfgss.com/conversations/128127/

First port of call would be to bounce on saddle whilst sitting on it, second twisting with big spanner.
If its aluminium caustic soda could be next, may be even gentle heating although that damages paint.

Tried everything anyone’s ever written or filmed about seatpost removal (except reamer, pillar drill etc which I don’t have access to). So now it’s fizzy time.

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I’ve had good results just with a hand drill. Try that before screwing up your paint work

It looks a bit late for that

It is indeed a bit late to avoid fucking up the paintwork. About 15 years late by the look of things. Bought the ‘bike’ for £20 and am hoping to salvage the frame and wheels, maybe even the rear derailleur. Been stood outside for many years.

This gon be good.

Can recommend using a surgical glove to cap off the seat tube. Forgot to take a pic but the result was a bloated waving rubbery hand thing filled with poison gas. Have taken the entire thing outside now.

36 hours and two changes of caustic soda solution later it’s still not budging. You can see how I’ve mangled the seattube while hammering, sawing and twisting the post in my naive first attempts.

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the only way is to wind it out while pulling. whacking it with a hammer won't work.

The trick is to ensure you're applying force in both directions at once - if you can only twist the post, you need to either apply a constant pulling force while twisting, or at least find a way to deliver some taps or whacks while twisting.

So whacking it should work, but only if you're twisting at the time

Paint still looks good, which is either a good thing, or your mix is bit weak.

Keep at it. Wear eye protection.

I got there after a couple of days extracting a similarly mullered post in an ancient pompino.

Gives me a chance to repost this gif...if it looks like below when you first put the juice in, you should get there soon

Ah, just seen you were watching the thread back then anyway!

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Lovely! I remember that gif but couldn’t find it when I was researching this. I’ve upped the strength and given it another go. I also learned how to make a gif, no small feat for a luddite like me!

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I'm getting some dry ice to do four frames if anyone wants to join in the fun.

I think it might be one of the only bits of bike fettling that a gif can do justice. Bubbly stuff.

What did you plug it with?