Seat Post Removal

[+paul]

I have started to strip down my MB Dronfield framed racing bike which I built in 1987, and originally sold in 1993. Everything has come apart so far apart from one of the dust covers on the crank (which broke when being turned), and the seat post which is well and truly stuck. I have removed the clamp bolt, and started to apply penetrating oil from the outside of the frame. I am going to take the chainset and bottom bracket off tonight and this will allow me to apply penetrating oil from the other end. Once this has soaked in, I have considered the following options as next step:

• Clamping the saddle in a vice, and applying rotational force on the frame (from the head tube, not the chain stays)
• Making a slide hammer, and trying to shock the seat tube out of the frame.

I am thinking the second option should put less stress on the frame, provided I can find a way to cushion the frame where I hold it.

I am sure I am not the first person to have this problem - can anyone offer advice about how to do this without damaging the frame? I don't mind if I destroy the seatpost in the process.

Thanks in anticipation!

 

[Robbied196]

You're definitely not alone its quite a common problem. Usually it happens with alloy posts which I assume is what you have. I'd give the penetrating oil and vice ago next but if it turns out to be really stuck, I've found over the years cutting them out is the simplest solution, with the least damage!

http://forum.ctc.org.uk/viewtopic.php?f ... st+removal

Here's one I cut out earlier

 

[biggs682]

oh dear thats not good

try using Plusgas rather than likes of wd40 etc etc , in the past i have had them cut out at quite an expense , but last couple have come out after a good soaking with Plusgas and a pr of stilsons attached to the top of the seat tube and some gentle attempted turns , always worth a try .

best of luck and let us know

 

[Ian Raleigh]

Heard so much about coca cola being poured through the bottom bracket shell
and keeping the frame upside down, well a friend tried this idea and put a condom
over the seat post and stretched it around the tubes and taped it up, this was to catch
the fizzy drink, two days later he emptied the seat tube and put the seat back on and with
a twist the seat post came free, utterly shocked at how well this stuff removed the corrosion.

I no longer drink cola after seeing this!

 

[+paul]

Re:

Thanks for the ideas! I have also heard about the coca cola approach. I'll try soime of the ideas you have shared, and let you all know how I got on. I'll also get some pictures up of the bike.

 

[+paul]

Re:

Solved! Before trying the more difficult approaches, I turned the frame over, clamped the saddle in a vice, and gently eased the frame. Without excessive force, it shifted. With the help of a friend managed to work it back and forth until it came out. We then put some scotchbrite on a dowel and drill and cleaned out the inside of the seat tube. I will clean up the seat post - it will still be useable, once I get the saddle clamp bolt loose!

I'll put pictures up on the Readers bikes sub forum soon (once I have a chance to give it a clean in the daylight).

Thanks again for the tips!

 

[oonaff]

Thank you for posting the conclusion.pleased you salvaged the seat post.

 

[b17ouch]

Re:

if seat post is badly stuck, coke etc not working and you dont want any damage/ stress to frame or burnt paint, there is a mechanic in Edinburgh who can remove them with up to 28cm inserted in frame, any frame/ seatpost material combination.
Not a cheap option(£30-£50) , + postage costs, but if frame worth saving and no secondary damage being done during removal ------ you will most likely need a new seat post though

 

[keithglos]

Re:

I believe the active ingredient in Coca cola is phosphoric acid.

Keith