In other words, the larger this second number is, the taller your motorcycle tire will be. For example, a tire that is written 130/90 means that it has a width of 130 mm and it is 90 percent as tall as the given width. When you calculate 90 percent of 130, that means it is 117 mm tall.

The 130 refers to the manufacturers stated width of the tire. Example: 130/90–16 (just the basics, there are several other things that may show in a tire size) 130 is the actual width of the tires in millimeters. 90 is the aspect ratio, width to height of the tire from the rim.

180 = the 180 designates the tire's width in millimeters, measured in a straight line through the tire from one edge of the tire's tread to the other.

The numbers (77) represent the load carrying capacity of the tire. In this case, 77 means 908 pounds. A typical load rating chart shows 47 or 386 lbs all the way up to 87 or 1,202 lbs. The letters (H) represent the speed rating of the tire. In this case, H means a top speed of 130 miles per hour.