The serial number of your bike is stamped under the bottom bracket of the bike. To find it, simply flip your bike over, and focus your attention on the part of the frame where the right and left pedals connect in the middle. You may need a flashlight to see the number, as it's not a sticker; the numbers are stamped directly into the metal. You can read more about how to locate your serial number via our journal post on the topic. If you have questions, feel free to give us a ring at 800.631.0630, and we'll walk you through it. In an effort to decrease bicycle theft, there are several options available for bicycle registration. The greatest chance of recovering a stolen bicycle is by having a registered serial number. We strongly recommend registering the serial number of your bike with us.