Here are the instructions for the 2013 but I think it's the same:
In order to adjust the speed/odometer calibration on your dash, you simply turn the bike on (you can leave it on its kickstand), and press the two dash buttons for a few seconds to get into the programming mode. You will then first see a “Pr†label with a set of numbers below it, which should read “405-00â€.
The “405†is the factor that’s used in the odo/speedo calibration, and it is the product of both the rear tire radius and the gearing (i.e. they are not entered separately). If it does not read “405â€, before you try changing it to better match your new tire size, please let me know the number that it does read (so that I can advise QC if it was entered in error).
As to what number you would change this to; if you know the new vs. OE tire radii, you could use these (as well as the difference in gearing ratios between the 25/132 OE belt and the 12/65 accessory chain), as an overall ratio by which to multiply the 405. Otherwise, it might just be a trial and error thing.
Please note that the labels on the dash buttons are backwards when you’re in the configuration screen; i.e. the bottom one labeled “adjust†does the selecting, and the top one labeled “select†does the adjusting; don’t ask me why Koso set it up this way…
As you keep pressing the select button (bottom one labeled adjust) to toggle between these numbers, it will take you to another set of numbers (labeled “Puâ€), which should read “02P†and should be left that way. The next set of numbers (without a label) should read “Li-5†and again should be left that way.
As mentioned below, once you change your calibration on the dash, it will not match the App at all, since that has its own calibration values that are not user adjustable and were supposed to match the original dash calibration values.
End
That's from Zero eng. What I did was to change the number by five each time (lower to lower reading) and used my GPS to determine actual speed. I kept doing this over a period of several days until I got the correct speed reading. Note that he says you can't make the app read to match the speedo.
Trikester