Key Codes

Honda motorcycle keys are delivered on a ring with a small metal tag that includes a string of eight numeric digits with values 1, 2 or 3. This number is the key code.

Any locksmith with a modern cutting machine should be able to produce a working key with the correct blank and the code.

Determining Your Key Code

Equipment and Supplies

1. A vernier, dial or digital caliper capable of reading in hundredths of millimeters
2. The key

Procedure

First, check your caliper by measuring the shoulder of the key. This is the un-cut part that runs up to the bow, which is where you'd hold it if you weren't using it. It should measure 9 mm.

Next, find the flat spot in the cut part of the key closest to the shoulder. Measure the distance to the same spot on the opposite side of the key, look up the digit in the table below and record it. Measurements may not be exact; anything within 0.5 mm on either side of the value in the table should be considered correct.

Measurement	Digit
7.0 mm	1
5.5 mm	2
3.8 mm	3

Continue measuring and recording the next seven flat spots for a total of eight digits.

Note that in some cases, a repeating digit will result in a single, wide flat spot on the key. The flat spots are centered at 1.8 mm intervals, so one wider than that is repeated.

The flat spot closest to the shoulder represents the last digit of the key code, so the numbers must be reversed to get the key code in the proper order. (For example, if you recorded 12312312, the key code is 21321321.)

Notes

These measurements were made from a Honda key delivered with a 2004 ST1300 that has only been used on the bike twice to make sure it worked. Its companion key, which has been used in the ignition for 14 years, was compared and found to be close.

-- MarkFeit - 29 Jul 2017