Stupid carbon seatpost

Roastie
Roastie Posts: 1,968
edited September 2009 in Commuting chat
My second attempt at a cross race yesterday out at Deers Leap Park.

During the recce I get a massive thorn that punctures the front. Minutes before the start a club mate thankfully helps me out with a spare front wheel; I make the start with just enough time to get my breath back. Then, towards the end of the first lap my stupid seat post snaps off. Gutting.

Mishaps aside, I had a great deal of fun and can't wait for the next one.

I'll be ordering a nice forged alu post to replace it! Will post pics tonight.

Comments

  • Cool, did it turn into knives pointed directly at your jacksie? 'Coz that's what I heard happened. :D
  • _Brun_
    _Brun_ Posts: 1,740
    I'm having problems with the carbon post slipping down the steel seat tube of my fixer. Am worried about tightening it any more in case it suffers a similar fate to yours.

    Tempted to replace it with something more traditional.
  • Roastie
    Roastie Posts: 1,968
    Cool, did it turn into knives pointed directly at your jacksie? 'Coz that's what I heard happened. :D
    Let's just say that my left butt cheek knew all about it. :o
  • _Brun_ wrote:
    I'm having problems with the carbon post slipping down the steel seat tube of my fixer. Am worried about tightening it any more in case it suffers a similar fate to yours.

    Tempted to replace it with something more traditional.

    Try Tacx carbon assembly paste.

    Hairspray may work too (as I have read. Somewhere).
    Swim. Bike. Run. Yeah. That's what I used to do.

    Bike 1
    Bike 2-A
  • Roastie wrote:
    Let's just say that my left butt cheek knew all about it. :o

    Oooh, ahhh, ayas!
    Greg66 wrote:
    Try Tacx carbon assembly paste.

    Hairspray may work too (as I have read. Somewhere).

    My FSA seatpost came with a little pouch of this stuff, they claim you can reduce clamping torque by 30% by using it. Also stops the post jamming in the down-tube. Also worth borrowing a proper torque wrench.
  • Old fashioned Elnette worked the best (says my ex-bikeshop techie bro) Slippy for a bit then sticks like shit when dry.
    Le Cannon [98 Cannondale M400] [FCN: 8]
    The Mad Monkey [2013 Hoy 003] [FCN: 4]
  • dilemna
    dilemna Posts: 2,187
    edited September 2009
    Carbon is a strong but brittle material so common sense tells me it is not the most suitable material to use for a seat post where it is under compression and considerable lateral and downward forces. A hi grade aluminium seat post is much stronger and less prone to failure IMHO. Carbon has it's place but not as a seat post.
    Life is like a roll of toilet paper; long and useful, but always ends at the wrong moment. Anon.
    Think how stupid the average person is.......
    half of them are even more stupid than you first thought.
  • I think it's fine on a road bike, I'd be less confident if I was bouncing on rough ground all the time. :shock:
  • Roastie
    Roastie Posts: 1,968
    One of the kids (who came 2nd in the juniors race before) looked at my post and said "now I'm scared to ride my carbon bike!" (a full carbon Massi crosser).

    Personally I don't think this proves that carbon fibre is a bad material - just reinforces the notion that components made from carbon fibre have a limited lifespan and don't give much warning prior to catastrophic failure.
  • Clever Pun
    Clever Pun Posts: 6,778
    Roastie wrote:
    One of the kids (who came 2nd in the juniors race before) looked at my post and said "now I'm scared to ride my carbon bike!" (a full carbon Massi crosser).

    Personally I don't think this proves that carbon fibre is a bad material - just reinforces the notion that components made from carbon fibre have a limited lifespan and don't give much warning prior to catastrophic failure.

    I see a DDD "How long will my bike last?" thread
    Purveyor of sonic doom

    Very Hairy Roadie - FCN 4
    Fixed Pista- FCN 5
    Beared Bromptonite - FCN 14
  • Roastie
    Roastie Posts: 1,968
    Clever Pun wrote:
    Roastie wrote:
    One of the kids (who came 2nd in the juniors race before) looked at my post and said "now I'm scared to ride my carbon bike!" (a full carbon Massi crosser).

    Personally I don't think this proves that carbon fibre is a bad material - just reinforces the notion that components made from carbon fibre have a limited lifespan and don't give much warning prior to catastrophic failure.

    I see a DDD "How long will my bike last?" thread
    Please, don't encourage him. If I read "K**ta" again, I will scream.
  • cjcp
    cjcp Posts: 13,345
    Clever Pun wrote:
    Roastie wrote:
    One of the kids (who came 2nd in the juniors race before) looked at my post and said "now I'm scared to ride my carbon bike!" (a full carbon Massi crosser).

    Personally I don't think this proves that carbon fibre is a bad material - just reinforces the notion that components made from carbon fibre have a limited lifespan and don't give much warning prior to catastrophic failure.

    I see a DDD "How long will my bike last?" thread

    :lol:

    Roastie - bad luck, fella. Fwiw, I'm going to use a Thomson Elite on the crosser. Bought it off CRC last year.
    FCN 2-4.

    "What happens when the hammer goes down, kids?"
    "It stays down, Daddy."
    "Exactly."
  • I'd use carbon assembly paste for a seat post. It may help stop it slipping, but more importantly will stop it seizing to your frame, which is fairly inevitable if you don't use it and don't have the saddle in and out that often.
  • Roastie
    Roastie Posts: 1,968
    cjcp wrote:
    Thomson Elite
    Very nice! When is it going to be rolling? Will you make this weekend up at Waltham Abbey?
  • cjcp
    cjcp Posts: 13,345
    Roastie wrote:
    cjcp wrote:
    Thomson Elite
    Very nice! When is it going to be rolling? Will you make this weekend up at Waltham Abbey?

    Cheers. Waiting for some bits to come through. Hoping my first race will be 18 Oct.
    FCN 2-4.

    "What happens when the hammer goes down, kids?"
    "It stays down, Daddy."
    "Exactly."