Please have your frame serial number for this registration ready. This is a 9 digit alpha-numeric number located on your Z-series, S-series, and R-series bike. On the SUPER73-K1D, the bike's frame number is a 13 digit alpha-numeric number. For models RX, R, S2, Adventure Series, K1D, and ZX, it's located on the bottom bracket between pedal cranks. For models S1, Z1 and OG, it's on the top side or underside of the bottom bracket.