Advertise on

User Tag List

Results 1 to 2 of 2
  1. #1
    Join Date
    Oct 2010
    0 Post(s)
    0 Thread(s)

    What Size Seat Clamp?

    I just got a frame fitted for a 27.2 seatpost. I have never had a bike that has to have a seat clamp added to its frame before,

    MY QUESTION IS... do i need a seat clamp that is also sized 27.2, or since the clamp is going on the frame does it need to be larger

  2. #2
    Senior Member
    Join Date
    Apr 2009
    New Rochelle, NY
    My Bikes
    too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
    188 Post(s)
    1 Thread(s)
    Seat post clamps are sized by the outside diameter of the frame's seat tube, not the seat post which is the size of of the inside diameter. They are often sold in metric sizes, but these are actually rounded off equivalents of standard inch sizes, either 1-1/8", 1-1/4", or 1-3/8" (approx 28..6, 31.8, or 35mm).

    If the seat post is 27.2, odds are the seat tube is 1-1/8" if steel or 1-1/4 if aluminum or carbon, but you'd best either measure or check the spec sheet to be sure.
    Last edited by FBinNY; 11-10-10 at 10:37 PM.
    Chain-L site

    An ounce of diagnosis is worth a pound of cure.

    “Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

    “One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

    WARNING, I'm from New York. Thin skinned people should maintain safe distance.

Posting Permissions

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