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How do I determine the size of a bike I own?

Last Updated: Oct 31, 2013 01:52PM PDT
First, look over your frame to see if there are any stickers indicating its size (for example: 17, 19, M, L, 56, 58 etc...) If a sticker indicating the size does not exist, then follow these simple steps:

1. Measure the length of your bicycle's head tube. The head tube is the part of the frame that the front fork inserts into. It is the forward most part or 'tube' of the frame and it is arranged in a slight angle off of vertical. You will need to measure this length in millimeters.

2. Once you have the length of your bicycle's head tube in millimeters, you can then compare that length to the geometry chart for your corresponding year and model of bicycle. A geometry chart is a chart that lists all of the important measurements of your bicycle's frame in relation to each size the bicycle was made in. The geometry chart for your specific model and year (as well as other valuable information about your specific bicycle model) can be found in the archive section of the Specialized website. The archive section can be found by hovering your mouse cursor over the red Specialized banner in the upper left hand corner of any page on the website, then clicking on 'Bikes' then clicking on 'Archive.'

3. Once you have located your specific model and year in the online archive, click on the 'Geometry' tab located under the photo of your bicycle. This will show you the geometry chart for your specific model and year in accordance with all of the sizes the bicycle came in.

4. Locate the row in the geometry chart labeled 'head-tube length' and scan across the row until you find the measurement that matches the measurement that you took from your bicycle's head tube.

5. One you have found a match, scan to the top of that column and you will see the corresponding size of your bicycle.

Note: A serial number does not indicate the size or the model and year of a bicycle. We will not be able to tell you this information with only the serial number. If you do not know the model and year of your bicycle, you will need to find it manually via the photos in the online archive.
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