There are many rims and tires on the market, but not all tires are designed to fit all rims, since the sizes of each vary. Pairing tires and rims can seem like a daunting task, but once you know how to measure their size, you'll be able to decode the numbers and get rims and tires that work together.
Rims are measured in inches, and the size of the rim is usually stamped into it on the back of the hub. The measurement is made from the top of the rim straight across to the bottom. Common rim sizes include 15, 16 and 17 inches. Rim size will vary depending on the make and model of the car and manufacturers may release different models of the same car with different rim size options.
Tire sizing is measured in three ways with three separate numbers. The first is the width of the tire from one outer edge to the other. The second is the ratio of the height of the tire to its width. The third refers to the rim diameter that the tire is designed to fit.
What to Look For on Your Tire
The measurements on a tire are marked consecutively on the sidewall and are separated by forward slashes. Measurements usually appear in raised black lettering, but they may also appear in white lettering. A tire marked 225/65/16 will have a diameter of 225mm from the outer edges of the tire. The sidewall of the tire will be 65 per cent the total width of the tire. Finally, the tire will fit a 16 inch rim.
Tires designed to fit a specific rim size may be able to fit other rim sizes. However, not all tires will fit all rim sizes. A specialist can help you make sure your rims fit the tires and vice versa.