View Here : How Tire Sizes Work
Tire Width. Is the width of the tire measured in millimeters from sidewall to sidewall. The first three-digit number in the tire size refers to the tire width. For instance, in a size P215/65 R15 tire, the width is 215 millimeters.
AA is the aspect ratio or profile of the tire, which expresses the tire’s height as a percentage of its width. X is a letter indicating the tire’s internal construction. DD is the diameter in inches of the wheel that the tire is intended to be mounted on. An example of a tire size written in this format is 225/50R16.
How Dirt Bike Tire Sizes Work: Breaking Down Numbers. Doing some more math, we can take the first tire’s width of 4.330 inches and multiply it by 90 percent to determine that the 110mm tire’s sidewall height is just under 3.9 inches (3.897) and the 120mm tire’s sidewall height is just under 3.8 inches (3.779).
The measurement is the tire's section height, and also referred to as the tire's series, profile or aspect ratio. The higher the number, the taller the sidewall; the lower the number, the lower the sidewall. We know that this tire size's section width is 225mm and that its section height is 50% of 225mm.
ATV tire sizes work in much the same way as automotive tire sizes. Each tire features three distinct numbers printed on the sidewall. It will look something like this: 27x11R 12.
Tire Tech: How to Read Speed Rating, Load Index & Service Descriptions Using a P195/60R15 87S tire size as our example, the 87S at the end of the size represents the tire's service description. A service description identifies the tire's load index and speed rating.
Wheel diameter: The next number tells you what size wheel the tire will fit. Common numbers include 15 or 16 for cars, 16-18 for SUVs and 20 or higher for many trucks. The size is measured in inches. Load index: This tells you how much weight the tire can bear.
How Tires Work. This is described as a percentage of the tire width. In our example, the aspect ratio is 75, so the tire's height is 75 percent of its width, or 176.25 mm ( .75 x 235 = 176.25 mm, or 6.94 in). The smaller the aspect ratio, the wider the tire in relation to its height.
I needed to teach my boys how to select tires so I thought I would share with the world. Why not, right? Lydia was an awesome camera operator!
The tire size "P225/45R17 91V" may not mean much to the average person, but to tire geeks like us it speaks volumes. Read on to learn how to crack the tire code with this handy guide dedicated to tire types, sizes, and construction.