Hi i have a stuck seatpost that will not budge.Ive used wd 40,GT 85 brute force but no cigar yet.Any advice would be greatfully received.I have also drilled a hole through seatpost to get some better leverage but still stuck.After all suggestions even if they are stupid.
Cheers Ian
Tie the seat to a tow-bar on a land rover and tie the rest of the bike to another land rover.
You asked for stupid!
Boiling water And brute force - twist and twist some more
had to extract a mate's once.
hacksaw blade screwed into a batten of wood and a lot of patience and hand eye coordination.
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plus gas.
try pouring a boiling water over the frame/seat tube.
I like the land rover.Or how about a workshop vice and use frame for leverage ?
What materials ?
I did as stoner shows on a customers beloved ti frame cost them a fortune it did but saved it !
If steel with an alloy post you could try caustic soda from the bb hole
If its carbon in alloy brute force and itll probably break
If its alloy in alloy - clamp tight in a vice and use the frame a a lever
clamp seatpost in a vice, use frame as lever to turn
Done the same as stoner on alloy frame with alloy post, three cuts down the length of a long post. A LOT of patience needed and if you use this method you still need to prize the sections of post away from the frame by tapping a screwdriver down between the frame and post.
http://teammaxbo.blogspot.co.uk/2010/12/caustic-bike.html
Did this with my Plug after all else had failed.
Worked a treat, here's the post afterwards...
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Plus Gas or similar penetrating oil applied regularly over a long period often works if you have the patience.
Stoners method definately works but needs patience. Saw through the post just above the frame and then saw several points right the way down the length of post still stuck in the frame, and then use a flatblade screwdriver to fold the slithers in on themselves. Write off a day and you will get there, just be careful you do not go through the frame and don't be looking for the final result too soon.
How do you get a seatpost stuck in a frame? (not the start of a joke btw)
Brake-neck, i was told that because of the different chemical properties of the different materials involved, what happens is that once water gets between the seattube and seatpost you get a very small electrical flow that effectively spot-welds the two together. That's why i always use a good grease to put a thin film on the seatpost, and redo it every few months as i once had it happen to me with a steel frame and alloy seatpost.
I had to do what Stoner did with a stuck carbon post. A little patience and it gets the job done and saves your frame. Will work on alloy posts too but will take a little longer that's all.
this thread has just remined me that my Thomson Post in my Rock Lobster hasn't been moved in about a year.......just removed and lo and behold it's a bit surface chemically rusty around the base, so cleaning off and about to regrease 🙂
thankyou STW
use fire. heat it up. cocks up your paint tho :/
Yup - hacksaw method worked for me on a second hand Kona Lavadome, waaaaay back in the day. Just wrapped the blade in rags rather than actually doing it porperly and making a tool though 🙂
Stoners hack-saw method reminded me of cutting the leaf-spring bolts off a Capri many years ago. 🙂
From the book of Sheldon Brown [url= http://sheldonbrown.com/stuck-seatposts.html ]14 Ways[/url]
Plus gas, but also from the other end, i.e. remove the BB and spray it into the seat tube via the BB shell. Or through the bottle cage bosses on the seat tube.
What finally got mine moving was using a huge sledge hammer to knock the post into the frame, it only moved 5mm put it was enough to start being able to twist it. One it was twisting it was just a couple of hours of effort to work it out.
Spooky its out now. shoutrd at it & brute force made it fly out.Cheers everyone for your advice.
muddydwarf - MemberBrake-neck, i was told that because of the different chemical properties of the different materials involved, what happens is that once water gets between the seattube and seatpost you get a very small electrical flow that effectively spot-welds the two together. That's why i always use a good grease to put a thin film on the seatpost, and redo it every few months as i once had it happen to me with a steel frame and alloy seatpost.
The short version of that is galvanic corrosion. Google it for more.