Seat post rusted and sticking

Figured I’d pop my head back in here (since I haven’t, again, been here for a while). I believe I am guilty of letting my MUni get a little rusty over the last year. I’ve kept it under an overhang at the side of my house, but the tube the seatpost goes in on the frame has rusted to the point where I can’t move my seat up or down at all. I can’t even wiggle it.
I’ve tried putting bicycle oil down the side in hopes it will sink in and unstick it, but it obviously hasn’t worked.
Are there any other products or ideas one would recommend using?


Maybe hold it upside down, plug the seat post so it will hold some ice water, heat the frame tube so that it expands to break the rust free. Only enough water for the seat tube and none in contact with frame tube.

Most plumbers will use some type of wrap around heat shield while heating copper tubing for soldering.

I’ve used a product from Gunk called Liquid Wrench. It’s a from of penetrating oil.

I was able to remove a frozen pedal from a 30 year old uni crank arm using liquid Wrench. I would apply it and let it soak for while; maybe remove the seat and tap lightly on the base with a hammer. Give it time, it should free the post.

Good Luck!


Thanks for this refernce Eric. I had not heard of the ammonia trick for aluminum posts. Will have to keep that one in mind.

Thanks for the suggestions. I’ll try a few of these as soon as I can.

I’ve been so busy with school and work that I haven’t been able to ride as much as I would like to in recent months. :frowning: