Knowing your Cannondale's serial number is like knowing the bicycle's middle name. The serial number gives important information about when the bike was manufactured to help accelerate the process of acquiring replacement parts and other general repair. The serial number also uniquely identifies the bike, and when the serial number is registered, can help to identify and reclaim stolen bikes. Locating a Cannondale serial number is simple and can make life dealing with your bike easier in the long run.
Look at the place where the chainstay connects in front of the rear tire. The chainstay is a pair of tubes that extend from the bottom of the frame and run parallel to the chain. This is the place where the serial number should be for the majority of Cannondale bicycles.
Look on the underside of the chainstay on both tubes nearer the rear tire. Also, look on the underside of the seatstay, which connects the part of the frame that connects the middle of the frame under the seat to the middle of the rear tire. This is where the serial number was placed for bicycles manufactured between 1986 and 1992.
Look on the backside of the seat post, which is the part of the frame that connects the seat. This is where the serial information should be for the Cannondale Raven models.
If your bike is stolen, register the serial number with the Just Stolen website to aid in its retrieval.