How do you find a serial number on a bicycle?

Most bicycle manufacturers print the serial number under the bottom bracket that connects the two pedal cranks. The bicycle needs to be turned upside down to read the number.

Other possible serial number locations include the headset by the handlebar mount or on one of the rear stays close to the rear wheel hub. Some manufacturers put the serial number on the seat down-tube just above the cranks or on top of the cranks.

The serial number is necessary to register the bicycle, which is the best method to help in recovering it should it be stolen. Most police departments use the registered serial number to find stolen bikes.