Seatpost seizure

[donaldbmcintosh]

A cautionary tale about what not to do if you find your seatpost is stuck.

Thought I would share the lessons learned!

https://www.donaldmcintosh.net/blog/seizedseatpost

[robbie]

Ha ha.
The seatpost on my mtb was completly seized just a few weeks ago. I just undone the clamp sprayed some oil down it and rode it for 2 weeks without the clamp. Eventually on a long ride it stared to slip down. Easy peasy!!

[Wotsits]

Patience is definitely a virtue with stuck seatposts...

There's a guy who actually specialises in this sort of thing
http://theseatpostman.com/

[donaldbmcintosh]

Nice idea robbie. I don't think that would have been sufficient to free up my seatpost, but I will never know now.

[Zippy]

I once got a seatpost properly stuck, think in my youth I either jammed an oversized post in, or it was just electrolytic corrosion (alu post in steel frame - these days I'm far more careful as to what materials I interface and use appropriate protection/barrier methods as applicable). After the normal bits of brute force and penetrating oils failed to work, it got a bit more agricultural

So I started with trying some brute force methods. I made up a star nut with eye bolt.



I then started by stripping the bike down, covering it in some rubber to protect the frame, and using the car with some ratchet straps to try and shock the seatpost out... unfortunately the strap kinda snapped. SIlly idea - don't try this at home kids



So more sensibly, a friend had some sailing gubbins and random scrap steel, so we rigged up a pulley system and mechanical advantage.



And then applied some heat.



And hey presto, it slid out.



These days I'd probs saw it out, or try one of those fancy space heater doodahs / cold pack things for bearing installation, or something. Live and learn

[benp1]

So what's the best thing to put between a steel frame and an ally seat post?

[Zippy]

So what's the best thing to put between a steel frame and an ally seat post?

I think lanolin was the conclusion I came to eventually. Obviously any barrier between the two different metals is better than none, e.g. copper grease etc.

I tend to avoid it where I can, I have a titanium post in my titanium frame

[chris n]

titanium post in my titanium frame

Ever heard of galling?

[fatbikerbill]

+1 for http://theseatpostman.com/

[Zippy]

titanium post in my titanium frame

Ever heard of galling?

Yes - and experienced it first hand (not on bicycles) - twas a right pita Who knew aluminium could suddenly become so difficult to drill out

[Mariner]

Although Al and ti are almost opposite ends of the potential difference scale they both have the ability to oxidise and will sit together in dry conditions.
In order to produce galvanic action you need something to act as an electrolyte.
Has anyone done a study of the usual greases we/I reach for when installing a seat post?
Shimano white anti-seize is my default.
I think silicone based ones might be worse but might be mixing that up with thermal transfer.
Also never had a problem with a hard anodised(?) Thomson seat post in a ti frame. Does the type of anodising make a difference?
After a comment on BB I did start to wipe grease into the seat post slot under the clamp.

[sean_iow]

This is from the Thomson website

A very light coat of grease is okay. Do not use anti-seize, as it can lead to slipping. To prevent sticking the post in the frame, remove, clean, and re-install it every 90 days. Do not use grease in a carbon fiber frame.

My current frame has an EBB so when I change ratios/adjust the chain tension I usually have to adjust the saddle height so the post is moved more often than every 90 days. My new frame is ti but with alternator drop-outs and I have a new Thomson post so I'll have to keep on top of the maintenance.

[Oli.vert]

This is from the Thomson website

A very light coat of grease is okay. Do not use anti-seize, as it can lead to slipping. To prevent sticking the post in the frame, remove, clean, and re-install it every 90 days. Do not use grease in a carbon fiber frame.

I'm guessing they're saying that in regards to use with their own seat-clamp, a thing of great beauty but little clamping force. Especially with the cheese-metal bolt they use, with that daft domed caphead. Light it maybe, but that's no excuse for using cheese.

Anti-seize still installed and the post-clamp replaced with a burly Hope one. And no more slipping.

[Bearbonesnorm]

When I was at college in that there London, I had a lecturer who always said, "never put anything together without first lubricating the surfaces, you wouldn't do it to your girlfriend so don't do it to anything else"

[Oli.vert]

When I was at college in that there London, I had a lecturer who always said, "never put anything together without first lubricating the surfaces, you wouldn't do it to your girlfriend so don't do it to anything else"

It seems that a new universal condition for action has been found, the How much would you do it to your girlfriend? test. Would the graduations be: Oh loads, a lot, some, a little, not at all. ?

Now, back to the question of greasing your seatpost. Fnurk.

[JohnClimber]

+3 for the seat post man.
Got a Thompson seat post out of a To frame in no time and without a mark.

[Blair512]

Didn't know about the Stirling Bike Doctor, will check him out next time I need a bike shop. My usual shop keeps selling me shiny things when I go in

[Mariner]

remove, clean, and re-install it every 90 days.

That should just coincide with having my RS forks serviced - not.

[Dave Barter]

The seatpostman +5

[johnnystorm]

Spurred on by this thread I went and checked my Thomson post in a Ti frame. Popped straight out thank God so fresh grease on refitting!

[AlasdairMc]

I’ve removed a couple of stuck posts, both cheap posts (luckily). First one was alloy in a steel frame which was horrible, but then having honed my technique the second one coming out of a Ti frame was much quicker. Lesson learned...