Stuck seatpost?
Author
Discussion

okgo

Original Poster:

42,126 posts

227 months

Tuesday 7th April 2015
quotequote all
I've tried penetrating oil and still nothing, wondering what else i can do as I need to lower the saddle as its playing up my achilles riding it!

I have lost the seatpin and still it hasn't budged in two weeks, I have tried a hammer, and just wondering if I'm missing some wonder trick for freeing it?

untakenname

5,350 posts

221 months

Tuesday 7th April 2015
quotequote all
What material is the seatpost and frame? Plusgas works really well on metal on metal, if its fully seized in a carbon frame then you may have to use a reaming tool which takes ages. If it's an aluminum post in a steel frame then you can dissolve the aluminum or try heating the frame then cooling the seatpost with plumbers spray.

okgo

Original Poster:

42,126 posts

227 months

Tuesday 7th April 2015
quotequote all
Its a steel frame with what I assume is an alu post...where would I find details of melting biggrin

WarrenG

345 posts

226 months

Tuesday 7th April 2015
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This will be interesting, I've got a Alu seatpost stuck in an Alu mtb frame, if there's a best method for that I'd be interested to know it!

Herman Toothrot

6,702 posts

227 months

Tuesday 7th April 2015
quotequote all
In that scenario I'd put the seat post in a vice and turn the frame after having sprayed plumbers freeze spray only on the post.

richardxjr

7,561 posts

239 months

Tuesday 7th April 2015
quotequote all
Leverage (in a vice or through the saddle rails), ammonia, or caustic soda.

Only use the latter 2 for an ally post in a steel frame though.



okgo

Original Poster:

42,126 posts

227 months

Tuesday 7th April 2015
quotequote all
richardxjr said:
Leverage (in a vice or through the saddle rails), ammonia, or caustic soda.

Only use the latter 2 for an ally post in a steel frame though.
I don't have access to a vice, so caustic soda, how would I apply it?

fromage

538 posts

232 months

Tuesday 7th April 2015
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I had the same issue and just ended up selling the damn thing on ebay

jpringle819

734 posts

268 months

Tuesday 7th April 2015
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I had this and ended up stripping down the frame and taking it to an engineering company in the hope they had some sort of machine to grind it out. They got their apprentice to do it with a hacksaw blade cutting slots into the inside of the seat post and then eventually collapse the post in on itself, took him a couple of days apparently.

WinstonWolf

72,863 posts

268 months

Tuesday 7th April 2015
quotequote all
jpringle819 said:
I had this and ended up stripping down the frame and taking it to an engineering company in the hope they had some sort of machine to grind it out. They got their apprentice to do it with a hacksaw blade cutting slots into the inside of the seat post and then eventually collapse the post in on itself, took him a couple of days apparently.
That's how I'd do it, it only needs one slot then you can fold it in on itself with a chisel.

One word of warning, I know what I'm doing biggrin

okgo

Original Poster:

42,126 posts

227 months

Tuesday 7th April 2015
quotequote all
How do you mean, cut the top off, and then cut down? I don't know how much post there is in the frame is the other issue!

WinstonWolf

72,863 posts

268 months

Tuesday 7th April 2015
quotequote all
Get a coat hanger or something and make a hook on the end, insert it down the centre and pull back and mark. Withdraw and measure, you'll know how much seat post you're dealing with then. I wouldn't cut off flush, you want something to grip.

If it's ally in steel you can probably chisel it in on itself quite easily "if you're careful"!

Steve vRS

5,393 posts

270 months

Tuesday 7th April 2015
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It's a vice and two blokes that you need. That's how I got mine out!

http://www.pistonheads.com/gassing/topic.asp?h=...

Steve

MadDad

3,835 posts

290 months

Tuesday 7th April 2015
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I had an Alu post stuck in my Ti frame a couple of months ago, I tried everything from penetrating oil, to trying to cool the post, to hammering it, to putting it in a vice and using the frame as a leverage - nothing helped! I ended up spending about 4 hours with a fine hacksaw blade cutting the bloody post out...... frown

Mentioned it to a chap at the LBS who said take out the BB, turn the bike upside down and fill up the seattube with Coke then leave it for a few hours - apparently it works everytime!!

Tc24

533 posts

168 months

Tuesday 7th April 2015
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MadDad said:
I had an Alu post stuck in my Ti frame a couple of months ago, I tried everything from penetrating oil, to trying to cool the post, to hammering it, to putting it in a vice and using the frame as a leverage - nothing helped! I ended up spending about 4 hours with a fine hacksaw blade cutting the bloody post out...... frown

Mentioned it to a chap at the LBS who said take out the BB, turn the bike upside down and fill up the seattube with Coke then leave it for a few hours - apparently it works everytime!!
Coke trick is handy to know, I had to faff about with a hacksaw blade on my old MTB too. There's still some in there I think, but at least the new one fits over it smile