Giant Defy Composite 3 2013- seat post

pfjmat911
pfjmat911 Posts: 4
edited September 2013 in Road general
On checking the seat post, there is some wear to one edge despite tightening to recommended torques.
Does anyone know an alloy seat post which would fit? Is the Giant Vector which comes fitted only available in composite? I couldn't find an alloy version. Thanks in advance for any suggestions.

Comments

  • dwanes
    dwanes Posts: 954
    I don't fully understand your problem.
    What wear exactly? What has it got to do with carbon?
  • pfjmat911
    pfjmat911 Posts: 4
    The post is triangular in shape.
    On the two sides, rear end, there is a little compression where it clamps.
    I have not had a carbon seat post before, and want to be sure it has not been damaged by the clamp. I have seen articles about carbon seat posts cracking, and being damaged although tightened within the recommended torque.
    Hope that clarifies the problem.
  • dwanes
    dwanes Posts: 954
    Are you having problems with it moving when you are riding?

    I have the same seatpost. I wouldnt worry about damaging the seatpost, it is very strong.
    You would damage the frame around the clamp before damaging the seatpost.
    The seatpost is far strong enough. I am not 100% sure but I think some of these seatposts have an aluminium core with a carbon wrap around the outside.

    Is it a new bike?
  • letap73
    letap73 Posts: 1,608
    Sadly it sounds like what I did ( get giant specialist to check) - the seat post clamp was torqued to the recommendation, however it "compressed" the seat post. It will probably last awhile, however it will start an unholy creaking which you cannot ignore eventually the post will fail. You need a new vector seat post - it costs around £110 which you can get from any Giant stockist. Do not torque up the limit - make sure its enough to hold the seat post in position - this needs surprisingly little torque, although you have to be wary of putting too little torque - a slipping vector seat post can damage the seat tube easily.
  • pfjmat911
    pfjmat911 Posts: 4
    Thank you for the replies.
    I have gently rubbed down the "worn area", and it would appear that only the clear coat had worn.
    My LBS mechanic reckoned the post had not been compressed.
    I have applied the carbon assembly compound, and it is not slipping at about half maximum recommended torque.
    I will listen out for any "creeks".
    Thanks again for your assistance.
  • spankwilder
    spankwilder Posts: 169
    pfjmat911 wrote:
    Thank you for the replies.
    I have gently rubbed down the "worn area", and it would appear that only the clear coat had worn.
    My LBS mechanic reckoned the post had not been compressed.
    I have applied the carbon assembly compound, and it is not slipping at about half maximum recommended torque.
    I will listen out for any "creeks".
    Thanks again for your assistance.

    Tightening torque on those posts are either 4-5 or 5-6nm IT NEEDS TO BE TO TORQUE If you've got marks on the post it is due to taking one bolt all the way to torque and then the other one - both bolt need tightening bit by bit. If you under torque them you run the risk of the post destroying the frame.
  • geordieboy
    geordieboy Posts: 8
    OP, listen to spankwilder or you will destroy your frame. This happened to me (same bike as yours) Lbs replaced frame free of charge as it was them who had set up bike.

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