Advertise on Bikeforums.net



User Tag List

Results 1 to 10 of 10

Thread: seatpost clamp

  1. #1
    05 Roubaix Comp Double
    Join Date
    Dec 2002
    Location
    So Cal
    My Bikes
    2012 Trek Madone 6.2
    Posts
    4,657
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    seatpost clamp

    If my seatpost is a 27.2 then would i use a 28.6 seatpost clamp?
    Touch every 3rd person and you'll find an idiot.

  2. #2
    Senior Member Michigander's Avatar
    Join Date
    May 2005
    My Bikes
    Giant ATX 1200, Schwinn Peleton
    Posts
    1,727
    Mentioned
    11 Post(s)
    Tagged
    0 Thread(s)
    I'm not sure, but when I worked at a shop, we just had a big box full, and we test fitted them until we got a match.
    Last edited by Michigander; 04-19-06 at 12:07 PM.
    Bring back the Sig Test!


    (\__/)
    (='.'=)
    (")_(")

  3. #3
    You need a new bike supcom's Avatar
    Join Date
    Aug 2002
    Posts
    5,434
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    You use a seatpost clamp that is sized to the seat tube, not the seat post.

  4. #4
    Senior Curmudgeon
    Join Date
    Jan 2005
    Location
    Directly above the center of the earth
    My Bikes
    Electra Townie 1-speed with basket & fenders
    Posts
    3,305
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by supcom
    You use a seatpost clamp that is sized to the seat tube, not the seat post.
    Spucom's right, but the OP's size diff sounds about right.

  5. #5
    Back in black cydewaze's Avatar
    Join Date
    May 2005
    Location
    Maryland
    My Bikes
    Trek OCLV, Scattante XLR, Jamis Dakar Expert, Alpinestars Al-Mega, Trek 9700
    Posts
    4,253
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by FarHorizon
    Spucom's right, but the OP's size diff sounds about right.
    That depends on the frame/material. My OCLV takes a 27.2 post and a 35mm clamp.

  6. #6
    Senior Member Old_Fart's Avatar
    Join Date
    Mar 2006
    Location
    In a cardboard box by Alki beach.
    Posts
    347
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I have two bike with 27.2 posts and they have different clamp sizes. One is a 30mm and one is a 31.6, I believe. Best to measure it or take to your LBS.

  7. #7
    Senior Member
    Join Date
    Jun 2005
    Location
    Washington DC
    Posts
    965
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I have two bikes with 27.2mm seatposts and 31.8mm seat collars.

    What kind of bike is it? Manufacturer's website might have the info.

    Also, if you have a clamp-on front derailleur, the answer to your question might be stamped on the inside of the front derailleur clamp.

  8. #8
    Senior Member Old_Fart's Avatar
    Join Date
    Mar 2006
    Location
    In a cardboard box by Alki beach.
    Posts
    347
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    The clamp-on derailleur thing may be wrong, too. My Cross-check has a seat tube that is tapered/butted on the outside. It has a 27.2 post, a 30mm clamp, and a 28.6 derailleur.

  9. #9
    05 Roubaix Comp Double
    Join Date
    Dec 2002
    Location
    So Cal
    My Bikes
    2012 Trek Madone 6.2
    Posts
    4,657
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by same time
    I have two bikes with 27.2mm seatposts and 31.8mm seat collars.

    What kind of bike is it? Manufacturer's website might have the info.

    Also, if you have a clamp-on front derailleur, the answer to your question might be stamped on the inside of the front derailleur clamp.
    05 Roubaix but it doesnt list the size.
    Touch every 3rd person and you'll find an idiot.

  10. #10
    Senior Member
    Join Date
    Jun 2005
    Location
    Washington DC
    Posts
    965
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by shokhead
    05 Roubaix but it doesnt list the size.
    It does list the front derailleur clamp size as 31.8, though. I'd bet that's your seat clamp diameter, too. Take it to a shop or email specialized to be sure.

    edit: Hey, it's not one of those teardrop shaped seat tubes, is it? Those take a special clamp from Specialized.
    Last edited by same time; 04-20-06 at 08:36 AM. Reason: and anudda thing

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •