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Bike Education

The Bike Cave has lots of information to help you bike safely in San Marcos.  We offer hands-on repair instructions from trained technicians, self-directed maintenance tutorials and classes on repair and safety.



Various locations of bicycle serial numbers
By Bike Index - Own work, CC BY-SA 3.0

Locating your Bike's Serial Number

A bicycle serial number is a unique set of letters, numbers, and sometimes special characters manufacturers engrave on every* bike frame. While they can be almost anywhere on the bicycle’s frame, there are several common locations.

  1. The most common location for a serial number is on the bottom of the bottom bracket shell. This area can be located by turning the bike upside down and looking where the cranks connect to the frame.
  2. A less common location is the non-drive side frame drop out. This can be located by inspecting where the bike’s rear wheel connects to the frame on the side away from the gears and chain.
  3. Another possible place to find the serial number is on the head tube of the bike. This can be located by inspecting the frame under the handlebars.

*Some very old bikes and some European bikes are not manufactured with serial numbers.