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  1. #1
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    Cracked Carbon fiber seat post!

    Hello guys and gals, this is my first posting in the Mechanic's thread so lets see if you guy's can help me here with a situation I have. I have a specialized Roubaix that I have ridden for 1,300 miles I weigh in at 285 lbs started riding at 460 lbs on another bike and started riding the rubay at around 330lbs, small history out of the way. The other day I heard a clicking sound while pedaling while going over uneven pavement, lo and behold I found that I over tightend the seat clamp a bit to much ( Yes besides I way a ton..) and the carbon fiber fact seat post finnaly cracked Longitudal ( up and down ). Its a hair line crack that appers to be on the surface, I am an auto tech by trade so busted out the borascope and saw that the crack isnt showing internally. Granted I know how carbon fiber can be damaged and not show, but if I stick a wooden dowel up inside and bond with some type of agent will it work to keep it from completely letting go ? I don't care about the weight as the extra few ounces can be lost via sweat and hard riding.. or do you all have any other suggestion ( besides buying a Thomson which won't happen till next month)? thanks for the help..

    Hector.

  2. #2
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    It might work. Consider however what broken carbon fiber looks like, and what that is going to do to your posterior. If you don't care about weight, but don't have the money for something nice, go to your LBS and ask them for the cheapest Kalloy or similar quality post they have. In my case it ended up being $10, and worked for what I put it on.

  3. #3
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    If I were you I would just replace the seatpost. Think about it, in the likely event that the crack propogates, do you want to be sitting on it when it breaks?

  4. #4
    Senior Member Scorer75's Avatar
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    I was on my bike when the seat post finally broke, doing about 20 mph. DON'T DO IT!!! It hurt, for a loooong time.

    I didn't know mine was damaged, it had no visible damage. One second I am riding in the drops, the next I am bouncing down the road.

    Bite the bullet, buy a Thomson seat post.

    You are welcome in advance.

  5. #5
    Decrepit Member Scooper's Avatar
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    I would not ride on a carbon fiber seatpost with a known crack, period. The risk of injury is just too great.

    The weight difference between a CF seatpost and an inexpensive alloy one is nothing compared to the combined weight of you and your bike. In fact, the relative weight of a chromed steel seatpost would be insignificant. Get the cheapest sturdy aluminum or steel seatpost you can find (that fits), and worry about the Thomson later.
    - Stan

  6. #6
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    Thanks for the replies fellas, was going to stick a wooden dowel with some industrial epoxy and jam it inside the full length of the post. I'll just have to wait till next week and get the Thomson seat post which I was going to get knowing that sooner or later the seat post would have started to fatigue due to my weight, in about another 60 to 70 lbs I won't have this issue.. lol.

  7. #7
    My bike's better than me! neil0502's Avatar
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    Quote Originally Posted by Scorer75 View Post

    Bite the bullet, buy a Thomson seat post.
    +1

    Ever want to father a child??

    BTW: Huge congrats on the weight loss. Keep it going!

  8. #8
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    Thank you Neil, biking don't forgive no one ! Thomson post is coming....

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