Seatpost seized......

San Marzano
San Marzano Posts: 132
edited January 2016 in Workshop
I'm wondering if anybody canhelp me.

I'm trying to raise the saddle height and the seatpost will not shift.

So far I have

1 Removed the saddle and modified the seat clamp for more leverage

2 Warmed the frame with an air gun.

3 Cleaned out the 'gap' between frame and seatpost and soaked with WD40.

Nothing!

Any more suggestions?

Thanks

Comments

  • keef66
    keef66 Posts: 13,123
    Is it an all carbon post or a cosmetic carbon wrapped alu post?

    Either way, carbon post stuck in an alu frame isn't a good combination; the alu corrodes and the resulting oxide fills the gap completely. Was the post treated with any kind of assembly paste before insertion? (My seat posts come out every few months for a wipe and another smear of grease or paste just to be sure)

    Are you prepared to sacrifice the post to save the frame?

    Only other thing I can suggest is stick the post in a bench vice and try rotating the frame. Risky if it's thin aluminium though; the frame won't have been designed with that kind of force in mind...
  • dj58
    dj58 Posts: 2,224
    I don't know if this stuff works, might be worth a try by removing the BB and spraying along the seat tube.
    http://www.sigmasport.co.uk/item/Effetto-Mariposa/CarboMove-200ml/286
  • 6wheels
    6wheels Posts: 411
    If it's still stuck...

    Turn bike upside down, remove seat tube bottle holder/ screws and blast some wd40 or coca-cola into the seat tube and leave for a day or two. Then stick your feet on the modified seat clamp and give it a good twist.
  • k-dog
    k-dog Posts: 1,652
    You're better using a proper penetrating fluid like Plusgas - works better than WD40. Turn the bike upside down and spray a bunch in there and see if that loosens it enough to get it moving.
    I'm left handed, if that matters.
  • g00se
    g00se Posts: 2,221
    Don't use plusgas on carbon - use the CarboMove mentioned above. It worked wonders for my stuck post. Works on metal too. Found out about it from the LBS who lent me the can.

    Reviews:

    http://road.cc/content/review/59182-effetto-carbo-move
  • lpretro1
    lpretro1 Posts: 237
    Contact The Seatpost man - http://www.theseatpostman.com/
    He's is brilliant - never known him not to get a post out
  • keezx
    keezx Posts: 1,323
    [url=http://www.bikeradar.com/forums/viewtopic.php?p=19774411#p19774411]k-dog[/url] wrote:
    You're better using a proper penetrating fluid like Plusgas - works better than WD40. Turn the bike upside down and spray a bunch in there and see if that loosens it enough to get it moving.

    This stuff like WD40 or Plusgas does nothing to aluminiumoxide , which is the problem.
    Ammonia does, but is hard to apply.
  • CiB
    CiB Posts: 6,098
    Most seatpost clamps fit nicely into a roadside drain, so it's worth trying that to get extra leverage. On mine it was so stuck that it snapped the clamp off the post, so at least it was then okay to scrap the post to get it out. Brute force and a spare pair of strong arms did it in the end.
  • keef66
    keef66 Posts: 13,123
    [url=http://www.bikeradar.com/forums/viewtopic.php?p=19775427#p19775427]CiB[/url] wrote:
    Most seatpost clamps fit nicely into a roadside drain, so it's worth trying that to get extra leverage. On mine it was so stuck that it snapped the clamp off the post, so at least it was then okay to scrap the post to get it out. Brute force and a spare pair of strong arms did it in the end.

    Genius! Hopefully I never have to use this tip, but if I do there's a drain right at the end of the drive.

    (might as well use it for something; like the rest of the ones up our road it's permanently brim-full of leaves and gravel so it's sod all use as a drain. They used to be emptied regularly but it's austerity measures innit? Which will be no comfort to the poor sods at the bottom of the hill who receive the inevitable torrent of water / gravel / mud / leaves when it rains heavily)
  • Man Of Lard
    Man Of Lard Posts: 903
    Could you not give it a downward tap (not a clout) to attempt to break any bond? Obviously that would be applying force in an expected direction (in design terms) because you're normally sat on the saddle...

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