One - Open your owner's manual to the general information section. Here, you'll find detailed information describing the location of the engine serial number.
Two - Look for the serial number on the lower portion of the engine, which is called the crankcase. Newer Honda models (1990 and above) often have it stamped on the rear of the crankcase, usually close to the swing arm pivot point. Older models (earlier than1990) may have it stamped on the lower left or lower right section of the crankcase.
Three - Write the engine serial number down for further reference. The number should be in the following pattern, where X represents a letter, and # represents a number: XX##E - #######. E is a common designation for all engine serial numbers.
Four - Look at the first four digits before the E. These digits represent the motorcycle model number. The last character represents the year of the particular model. Refer to the Honda Motorcycle Model and Engine Code website for a list of these codes (see Resources).
Five - Read the seven digits after the dash. These digits convey information regarding the engine casing. This information is important when ordering engine parts for your specific engine. As motorcycle manufacturers often alter engines within a specific model of motorcycle, this serial number is important.
Six - Tell the Honda service center the engine serial number when ordering parts. This ensures the correct replacement part.