22
Jun
An example of tractor tire sizes expressed in the standard format would be. The first number is your overall diameter of the tire.
This measurement varies depending on the rim to which it is fitted.
What do numbers in tire size mean. Is the ratio of the height of the tires cross-section to its width. The two-digit number after the slash mark in a tire size is the aspect ratio. The two-digit number that usually follows the tires section width tells us the aspect ratio or tire profile measurement.
It is important that we understand tire geometry and be informed of the parameters that govern their performance. 245 Section WidthTread mm The section width is the width of the tire from one sidewall to the other measured in millimeters. The final number group the 18 is the size of wheel the tire fits.
In our example size the tire will fit a 18-inch wheel. Some manufacturers build off-road tires using inches instead of millimeters so you may see sizes like 3317 This simply means the total height of the tire is 33 inches and it fits a 17-inch wheel. If theres no letter before the first number you have a metric tire most commonly referred to as European size.
Its also measured in millimeters but may have different load capacity than a P or LT tire. TIRE WIDTH The three-digit number following the letter is the tires width from side to side looking at the tire head on in millimeters. Understanding Three Numbers in Tire Sizes The first number in a tires size say 225 is the width of the tire in millimeters.
You may see tires without these tire numbers meaning the tires profile is standard 82. In the size 25800-12 the meaning of the numbers is as follows. 25 - The overall height of the tire when mounted and inflated.
800 - The overall width of the tire when mounted and inflated. 12 - The diameter of the wheel this tire will mount to. The standard method of size expression is relatively simple but not as descriptive as metric.
An example of tractor tire sizes expressed in the standard format would be. 1- or 2-digit number. Diameter in inches of the wheel that the tires are designed to fit.
There is the rare exception of metric-diameter tires such as the use of the 390 size which in this case would indicate a wheel of 390 mm in diameter. Few tires are made to this size currently. The first number is your overall diameter of the tire.
In this example the tire diameter or height is 33 inches tall. The second number represents the width of the tire. In most cases with inch measurement tires the width will have a50 decimal after the initial number.
1 These are some of the most important numbers on any tire as they tell you how big your tires are. In this case the tire is 245 millimeters at its widest point when its mounted on a wheel of. The P stands for PMetric.
If your tire size starts with LT rather than a P then it identifies the tire as a Light Truck tire. 225 identifies the tire section width which is the measurement of the tire from sidewall to sidewall in millimeters. This measurement varies depending on the rim to which it is fitted.
Next you will find a slash and then another set of numbers. The aspect ratio sometimes called the tires profile. This number is a percentage that indicates the tires height vs.
In the example above the aspect ratio of our tire is 65 meaning that this tires height is 65 of its width. A smaller number means a lower profile and the height-to-width ratio is shown as a percent. For example if the aspect ratio is 90 that means that your tires cross-sectional height is 90 of its width.
If the tire has the metric alpha or low-profile inch numbering system the aspect ratio will appear immediately after the width. After the forward slash the next number on our example tire is 65. This is the tires aspect ratio or its percentage of width to sidewall height.
In this case 65 means that the tires height is. 28 x 140 states the approximate outer diameter 28 inches and the tire width 140 inches. Inch marking such as 28 x 1 58 x 1 38 approximate outer diameter x tire height x tire width is also common.
Inch sizes are not precise and lack accuracy.