Measuring rim width is a simple process that can be done using a few basic tools or by checking existing information.
To measure rim width directly, you can take a ruler, yardstick or tape measure and measure the distance from bead seat to bead seat. The bead seats are the points inside the rim where the tire's beads sit when the tire is mounted and inflated.
Alternatively, you can often find the rim width provided as part of the wheel size information. This size is typically stamped on the back of the wheel, or it can be found in your vehicle's owner's manual.
Methods for Measuring Rim Width
There are two primary ways to determine your rim width:
Method 1: Direct Measurement
This method involves using a measuring tool to get a physical measurement of the internal width of the rim.
- What you need: A ruler, yardstick, or tape measure.
- Where to measure: Measure the distance between the two bead seats on the inside of the rim. Do not measure from the outside edges of the rim.
- Important Note: Rim width is standardly measured from bead seat to bead seat, not the overall outer width.
Method 2: Checking Existing Information
This method relies on information provided by the manufacturer or printed on the wheel itself.
- Look for markings: Check the back of the wheel for stamped numbers and letters. The wheel size, including rim width, is often inscribed here.
- Consult your owner's manual: Your vehicle's owner's manual contains specifications for the original equipment wheels, including their size and rim width.
Why is Rim Width Important?
Understanding your rim width is crucial for selecting the correct tire size. Tires are designed to fit within a specific range of rim widths to ensure proper function, handling, and safety.
- Using a tire that is too wide or too narrow for your rim can lead to:
- Improper tire shape (rounded or stretched).
- Uneven tire wear.
- Compromised handling and stability.
- Increased risk of tire or wheel damage.
Knowing your rim width is an essential step for anyone looking to replace tires or wheels.
Example Rim Size Notation
Wheel sizes are typically expressed in a format like 17x7.5, where:
- 17 represents the rim diameter in inches.
- 7.5 represents the rim width in inches.
This notation confirms how rim width is included in the standard size specification.
| Measurement Aspect | Description | Typical Unit |
|---|---|---|
| Rim Diameter | The diameter of the wheel where the tire seats. | Inches |
| Rim Width | The distance between the tire bead seats. | Inches |
Measuring rim width is a straightforward process that ensures you can choose compatible tires for optimal performance and safety.
