wellerchap

This seat post is stuck in my steel frame Peugeot Optimum road bike (no idea for how long, it was a recent Ebay purchase.
I love the elegant styling of the swans neck design & would love to remove it in one (healthy) piece.
I've begun the penetrant dowsing method & have all the time in the world for it to drink in...there's no rush.
There's roughly 3 inches of straight post above frame level - does anyone know how much more may be in the frame?
Also, is it a recognised post & therefore easily tracked down to replace? I don't see any visible markings for i.d.

Eric S.

In the days of level top tube frames seat posts were very short compared to today. It's likely only 180mm long.

dsbrantjr

Get some Kano Kroil, it is your best chance at a penetrant-only solution.

alcjphil

I get it. The top of that seat post has an elegant appearance. However, if is well and truly stuck you may have to sacrifice it in order to save the rest of this bike. Penetrating lubricants can help, but still some brute force may be required to free that seat post which might destroy the top of the seatpost. . I faced the same dilemma years ago freeing up a seat post on a GT LTS. I worked on it for over a year, finally having to cut the post off and cut from the inside diameter of the post . I saved the bike, sacrificed the post. Do you want a bike or a useless seat post?

cyccommute 

No clue on the seatpost, although it looks a bit like a long layback Velo Orange Grand Cru. However, I think you may want to reassess whether or not it’s even worth trying to remove the post. The frame is showing some very concerning rust. The rust on the seatstay isn’t anything to worry about but every joint on the frame that we can see in the picture is showing rust. Not a little rust but rust that completely encircles the lug/tube joint. That’s concerning.

Bill Kapaun

You might be ale to get a rough idea by tapping the seat tube with a SMALL wrench or similar and listen to when the sound changes pitch/tone/different.

I'd give those rusty joints a workout with a wire brush to see IF you can tell how deep it goes.

3alarmer 

.
...just a couple of random thoughts. they may or may not help you.

1. the best penetrant, by far, is a 50/50 mix of acetone and automatic transmission fluid.

2. I have owned a couple of posts that were designed like that, and they did not work well. You can help them work better, by increasing the friction of the large flat surface on that curved top, but they tend to slip unless the bolt is tightened excessively. I just replaced mine with a different design.

3. when you struggle with trying to get it to break free, it helps a lot to install an old, junk steel saddle frame, or a crummy saddle you can sacrifice, into the post, Then you can pound and twist on the saddle frame, not the post clamp. If youi have access to a solid mounted bench vise, you can clamp the steel saddle frame in the vise, and twist the bike frame itself, to break it free of the post.

andrewclaus

If you plan on repainting, DOT3 brake fluid is also an excellent penetrant. But it will damage paint. I use it on auto suspension work with great results.

In any case, even with successful penetration, it's still going to take a lot of mechanical force. I hear aluminum swells when it oxidizes. The idea with a sacrificial saddle is a good one. Otherwise, an 18" or 24" pipe wrench on the post has worked for me. Be sure to use the front triangle for the opposing force.

Checking the oxidation at the BB shell before proceeding is a very good idea.

oldbobcat

A sacrificial saddle is unlikely to provide enough grip or leverage. I'd put that post in a bench vise, protected by wooden blocks, of course. Spray the inside with penetrant, let it soak for a few days, and then start with short, sharp twisting efforts on the frame. Resist the urge to use a hammer or cheater bar.

andrewclaus

But that takes patience!

3alarmer 

....this may be your opinion, but I can assure you that I've done this plenty of times, and in fact, keep an old leather saddle frame (minus the leather) hanging over on one corner of the tools pegboard for exactly this purpose. It works quite well, and you don't need any wooden blocks or other protections for the saddle frame, because it is not necessary to protect it. Why in the world would you think that grabbing a sacrificial saddle frame, attached to the post via the post's own clamp, and fixed on a bench vise, would have less "leverage" in using this method to twist the frame off the post ? It's the same operation. But by avoiding any clamping force directed from the vise to the post, it protects the post and clamp itself.

xiaoman1 

I will add turn the bike upside down and put the penetrant into the BB shell and give it a long time to work...you might even see some of it flowing out around the "downturned" seat post.
Good Luck, Ben

3alarmer 

.
...the other thing you can do is grab a MAPP gas torch, and use it to do several heating and cooling cycles, applying the heat to the aluminum post, to avoid smoking the paint on the frame. The expansion and contraction over several cycles will usually break the corrosive bond between the steel frame and the aluminum post, and it also helps your penetrant to wick in, if you apply it when the thing is hot. You should get it hot enough to smoke the oil, but not so hot that you damage the paint. If that makes sense ? It usually works, but sometimes posts can be pretty stuck in there.

Cool with something like Freeze Off.

grumpus

That's probably a result of inadequate flux removal before painting, it's likely to be superficial.

wellerchap

I hope you're right - time will tell.

wellerchap

That seems to be an American product - very expensive here in the UK.

wellerchap

I'm at the start of the process - loads of time to soak from both ends....best case scenario I'd love to save everything (Google "characteristics of Yorkshire people" to find out how we have a reputation for money-saving )....but I understand it's a process with many outcomes.

wellerchap

The bike cost me GBP23.....about same in dollars, maybe less, so I'm happy to take a chance.

wellerchap

It's OK.....I have a little bit of that

wellerchap

Thank you, yes - it's going in at both ends!

wellerchap

I like the sound of that.....hope so!

grumpus

I'm generally a fan of PlusGas but I'm not sure how effective it would be in this situation - possibly together with the repeated heating mentioned elsewhere.

cyccommute 

On a new (or newer) bike, it might be superficial. But this bike is around 30 years old and has significant rust elsewhere, in addition to a frozen post. It has rust problems.

squirtdad

other seat post removal approaches

I agree with doing a good rust check before investing time/effort on the seat post

some other seat post removal methods

ammonia soak, turn frame upside down an fill with as concentrated ammonia as you can find

thermal shock..... a product called freeze off combines penetrant and get super cold when applied...this is my go to for stuck things

from there it is destructive removal

lye soak to dissolve the seat post

cut top of seat post off and cut the seatpost out by cutting vertical strips out

oldbobcat

Been there, done that. Didn't work. Thanks anyway. The bench vise works if the bench is bolted to something solid, like the floor or wall joists. I wouldn't have brought it up if I hadn't already done it.