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  1. #1
    Nicole? Papa?
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    New seatpost seems very tight in my frame

    Have a nearly new Large 5 Spot which I'm building up and have bought a Thomson 27.2 seatpost, but when I tried to put it in the seat tube it seemed very tight.

    There doesn't appear to be any damage to the frame or the seat tube and I've felt down the frame with my fingers and it seems all smooth and fine.

    Don't get me wrong, it goes in, it's just very stiff. I'm going to try and wipe some grease over the post and inside the seat tube, but should it be this tight a squeeze?

  2. #2
    IPA
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    Suck My Wake
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    Lube the Tube

    Grease is needed on the seatpost, except in the case of a carbon post. It also helps to smear a little through the top portion of the seattube. The tubing tolerances are very specific, so it is going to be snug. Some grease will loosen her up...

  3. #3
    Amphibious Technologies
    Reputation: SCUBAPRO's Avatar
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    Quote Originally Posted by GeeTee
    Have a nearly new Large 5 Spot which I'm building up and have bought a Thomson 27.2 seatpost, but when I tried to put it in the seat tube it seemed very tight.

    There doesn't appear to be any damage to the frame or the seat tube and I've felt down the frame with my fingers and it seems all smooth and fine.

    Don't get me wrong, it goes in, it's just very stiff. I'm going to try and wipe some grease over the post and inside the seat tube, but should it be this tight a squeeze?
    Dunno bout you but I like a nice tight fit. but as you said, a little ky, errr grease, should help with the insertion though
    "The best you've ridden is the best you know" - Paul Thede, Race Tech

  4. #4
    Nicole? Papa?
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    ^^^I'm finding it hard not to laugh ;-)

  5. #5
    Fragile
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    Quote Originally Posted by GeeTee
    Have a nearly new Large 5 Spot which I'm building up and have bought a Thomson 27.2 seatpost, but when I tried to put it in the seat tube it seemed very tight.

    There doesn't appear to be any damage to the frame or the seat tube and I've felt down the frame with my fingers and it seems all smooth and fine.

    Don't get me wrong, it goes in, it's just very stiff. I'm going to try and wipe some grease over the post and inside the seat tube, but should it be this tight a squeeze?
    I wouldn't sweat it. It's possible that your Turner is on the small size of the acceptable tolerance, and your Thomson is on the large side creating a tight fit. Rarely, it has been reported of some extra welding material interfering with post insertion, but it sounds like you felt around and this is not your issue.

    I just built a 5 Spot and an RFX up, both with Thomson posts, and both fit slightly different with no issues at all.

    When do we get to see some pics?
    "It's easy to grin, when your ship comes in, and you've got the stock market beat; but the man worth while, is the man who can smile, when his shorts are too tight in the seat.'"

    -- Judge Smails

  6. #6
    Nicole? Papa?
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    But thanks for the advice. I guess I'm just used to less superior frames where the tolerances aren't so exact.

  7. #7
    mtbr member
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    paint?

    sometimes the paint around the outside of the seat tube is pretty thick so when the clamp is popped on it 're-sizes' the ID. Of course if the frame is raw I guess you have a tight one.

    DT

  8. #8
    No, that's not phonetic
    Reputation: tscheezy's Avatar
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    Did the previous owner run an undersized seatpost in the frame and crimp the top of the seat tube a smidge?
    My video techniques can be found in this thread.

  9. #9
    Bite Me.
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    Grease it - better to have it tight than a bit too loose.
    When I see an adult on a bicycle, I do not despair for the future of the human race. ~H.G. Wells

  10. #10
    mtbr member
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    "Did the previous owner run an undersized seatpost in the frame and crimp the top of the seat tube a smidge?"
    I think the same, is the slot at the top of the seat tube parallel?
    You can get your seat tube reamed a bit, if it is too tight, or wiggle your post in the end to open it up a tad (a little risky)
    Stay off the brakes

  11. #11
    Lay off the Levers
    Reputation: Bikezilla's Avatar
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    I once encountered a bit of a metal foil mask in the seat tube that made insertion difficult. I scraped it out with a flat head screwdriver.
    Faster is better, even when it's not.

  12. #12
    Let's roll.
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    Bend, Oregon. Proof you don't have to die to get to heaven.

  13. #13
    Captain Underpants
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    I don't think that is approved for aluminum.

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