stuck seatpost
- Thread starter M1K3
- Start date
Nerf Herder
Wheel size expert
I find several cans of WD ... over 3 or 4 nights and just letting it seep in will often work, where vices, hammers and general brute strength wont. Gotta avoid the temptation to touch it whilst its seeping in ... which I never seem to overcome 
baring that ... get mate with video camera ... go to your nearest bridge ... tie rope to seat ... tie other end of rop to railing and heave ho ... could win Funniest Home Video at least and get yourself a new rig.
baring that ... get mate with video camera ... go to your nearest bridge ... tie rope to seat ... tie other end of rop to railing and heave ho ... could win Funniest Home Video at least and get yourself a new rig.
By the sounds of it the post is sized in by corrosion of some description, might be worth lightly tapping the seat tube with a hammer, this way it will hopefully break the bond that has formed between the metals. Be careful not to clock it too hard otherwise you will bend the tube and lock it in! this may also allow the WD-40 to soak through!
what do you mean, tap it like straight down with a hammer? but if it's already lodged into the frame theres nowhere farther down for it to go.
Grip
Yeah, yeah... blah, blah.
Trust me... TWISTING is the worst thing you can do, despite the fact that it seems the obvious thing to do. In most cases it will simply make the situation worse because of the very real chance of spooling between the post and tube. It needs to be removed STRAIGHT out and it's probably going to mean you'll need a new post.
No no, tap 'around' the tube, to try and dislodge the bond between the two metals, as in the sides of the seat tube (not seat post)
If you have ever used a rattle gun its uses the same procedure, by inducing small high frequency shocks into the seized bolt/nut the bond becomes broken and allows the bolt/nut to be released/turn.
As its a bit impractical to attach a rattle gun to a seat tube you can use a small knocks from a hammer around the tube, this should produce a similar effect. if possible load up seat post axially (along the length) and tap away, hopefully this will free the post!
What material is the seatpost, and the frame? If it's aluminium, it's going to be tricky.
If you are going to tap on the frame, place a piece of wood on the frame, and tap on the wood so you don't damage the frame. It's probably better to tap the seatpost than the seat tube.
If I were you, I'd sacrifice the seatpost:
1. Get a bolt, drill a hole into the seatpost, stick the bolt in.
2. Invert the frame and spray WD40 into the seat tube and let it seep down to the seatpost.
3. With the frame inverted and secure, start tapping on the bolt.
You could also try heating the seat tube - assuming that you are not concerned about the paint / finish as you are restoring the frame - and keep tapping the bolt.
That would hopefully have the seat tube expand more than the seatpost and help free it.
Oh...and if you are using heat, don't forget that WD40 is flammable. I know "mechanics" who in their frustration have forgotten that.
If you are going to tap on the frame, place a piece of wood on the frame, and tap on the wood so you don't damage the frame. It's probably better to tap the seatpost than the seat tube.
If I were you, I'd sacrifice the seatpost:
1. Get a bolt, drill a hole into the seatpost, stick the bolt in.
2. Invert the frame and spray WD40 into the seat tube and let it seep down to the seatpost.
3. With the frame inverted and secure, start tapping on the bolt.
You could also try heating the seat tube - assuming that you are not concerned about the paint / finish as you are restoring the frame - and keep tapping the bolt.
That would hopefully have the seat tube expand more than the seatpost and help free it.
Oh...and if you are using heat, don't forget that WD40 is flammable. I know "mechanics" who in their frustration have forgotten that.
Last edited:
Tazed
Likes Bikes and Dirt
Use hot water (not boiling, but hot) to heat the seat tube (NOT the post).
It may help. If not, the bike will at least be clean...
Turner_rider
Likes Bikes and Dirt
Assuming the frame is steel of some sort and the bottom bracket shell is not sealed (Fat Chance style), take the cranks out and put a lot of WD40, or some other penetrating fluid (even coke works) down the inside of the tube and leave the whole frame and post upside down for a week or two.
More often than not this will budge most posts, it just takes time.
More often than not this will budge most posts, it just takes time.
Oppy
Likes Dirt
Hmm interesting. So at this point I should not state I used to be a shop mechacnic and this was one of our fall back practices. Our other last resort for alloy posts was to cut it off and use a hacksaw blade to cut throught the internal of the seat post in two places and effectively compress the post to get it out. I should add both of these are last restort practices but ones I have used sucessfully on more than one occasion. (The cut throught requires patients and a steady hand)
Anyhow good luck with the project. Post some pics so we can enjoy.
Grip
Yeah, yeah... blah, blah.
And maybe I should not state my experience either, eh?Hmm interesting. So at this point I should not state I used to be a shop mechacnic and this was one of our fall back practices. Our other last resort for alloy posts was to cut it off and use a hacksaw blade to cut throught the internal of the seat post in two places and effectively compress the post to get it out. I should add both of these are last restort practices but ones I have used sucessfully on more than one occasion. (The cut throught requires patients and a steady hand)
Anyhow good luck with the project. Post some pics so we can enjoy.
Oppy, you can state what you like and I never said twisting wouldn't work... just that it's the worst thing to do because if it doesn't work but does spool up then the situation ends up much worse than it would have been with a straight, axial removal.
i really don't care if the seatpost gets messed up as im getting a new one anywayAnd maybe I should not state my experience either, eh?
Oppy, you can state what you like and I never said twisting wouldn't work... just that it's the worst thing to do because if it doesn't work but does spool up then the situation ends up much worse than it would have been with a straight, axial removal.
the only thing im worrying about is medssing up the frame
i took the pedals out today and the post is sticking out into the place where the cranks and pedals are so could i use a hammer and hit the bottom of the seatpost a o you guys think that would work?
I'm surprised its sticking out into the bottom bracket. Anyway, if that is the case, make a wedge out of wood (rounded on one side to fit the bottom bracket) and tap it in. It should push the seatpost up.
Keep a careful eye on it as you don't want to bend the seatpost in the bottom bracket!
Not sure I would do that - more likely to ovalise the seatpost, which might make it harder to remove.