What does the tire size 90/90-10 mean?

[MaximusDella]

Tire size 90/90-10 indicates a tire height of 81mm. Here are the details about 90/90-10 tires: 1. Metric system: The 90/90-10 motorcycle tire uses metric measurement. 2. Tire width: The 90/90-10 motorcycle tire has a section width of 90mm, with an aspect ratio (the ratio of tire sidewall height to section width) of 90%, meaning the tire height is 81mm. 3. Tire type: The 90/90-10 motorcycle tire is a low-profile tire.

[DelAlexa]

I used to wonder what this code meant, until I figured out that 90/90-10 refers to motorcycle tire dimensions. The first 90 indicates the tire width of 90mm, showing how wide the tire is when viewed from the side. The second 90 is the aspect ratio, meaning the tire's height is 90% of its width, so the sidewall height is 81mm (90 multiplied by 90% equals 81), making it a medium-height tire. The final 10 means the rim diameter is 10 inches. These tires are commonly found on small scooters and lightweight motorcycles because the smaller wheels lower the overall height, making the ride more agile, stable in turns, and easier to park for city commuting. However, for long-distance highway rides, they might feel less supportive, as high-aspect-ratio tires offer better shock absorption but slightly slower handling response.