How to Measure a Bike Seat Post

An appropriately sized bike seat post is necessary for safe and simple riding. When pedaling a bike, your seat should be fit and adjusted so your knees are never fully extended at the lowest part of the pedaling cycle. This will provide an efficient stroke on each turn and prevent injury. The process of measuring a bicycle seat post is very simple and can be done by anybody, from recreational riders to professionals at a bike shop.

Things You'll Need

  • Measuring tape
  • Screwdriver
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Instructions

    • 1

      Remove the post from the frame of the bike. For some bike models, this requires you to pull an arm away from the post to release the seat. For other models, you will have to loosen a screw that holds the bracket securing the post in place. Once you have released the tension on the seat, pull the seat upward from the frame.

    • 2

      Hold the lowest numbered end of the tape measure at the top of the seat post where it meets the saddle rail. The saddle rail is located under the actual seat and sits perpendicular to the post.

    • 3

      Extend the tape measure to the bottom of the seat post.

    • 4

      Note the number or marking that is located on the end of the post farthest away from the seat. This is the length measurement for the seat post.