Odometer in chromed steel Ø 48mm. Threaded pin M12 x 1, K: 1.0, Ratio 1: 1. Black background. Bracket for fixing not included. To check the wheel ratio (K) of your motorcycle proceed as follows: Calculation of K: K = 10 X / U. X = number of turns made by the speedometer cable by turning the wheel 10 times U = wheel circumference. NB although most of the brands indicated mount instruments with this ratio, there may be some models that provide a different ratio, for this reason we always recommend that you inquire about the ratio to the wheel provided on your bike. For all the information for mounting and connecting the odometer click on the "INSTRUCTIONS" button. To learn more about the compatibility of mechanical odometers click here