Replacement part sizing

marchant Posts: 362
edited October 2008 in Commuting chat
Okay, this feels like a daft question, but how are bike parts measured? For example, stem length; are they measured in terms of overall length (black), or from mid-point to mid-point (red), or from the nearest point of the steerer tube to the nearest point of the bar? And what about seatpost clamps? Here's an example to try and illustrate my quandry;


Help me please, it's driving me crazy


  • always_tyred
    always_tyred Posts: 4,965

    Seatpost clamps measured in relation to the seat post diameter they are intended for use with.

    Frames, however, seem to be measured between any two random nodules positioned anywhere on the bike.
  • nicklouse
    nicklouse Posts: 50,675
    stems are center to center. cranks C to C, seat posts diameter of the post, seat post clamps the diameter of the seat tube (frame).

    Frame sizes ask the producer as as said above they vary.
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