80/100-18: This indicates the tire's dimensions. 80 is the width in millimeters, 100 is the aspect ratio (tire height as a percentage of width), and 18 is the rim diameter in inches.
M/C: This designates the tire for motorcycle use.
47P: This is the load and speed index. 47 refers to the load capacity, and P indicates the maximum speed rating.
){kind=link}
){kind=link}