To measure your wheel width accurately, you need to measure the distance between the tire bead seats on each side of the wheel, not the overall width of the rim.
Understanding Wheel Width Measurement
Wheel width is a crucial specification for determining proper tire fitment and vehicle performance. It is defined by the distance across the wheel at the points where the tire's beads (the edge of the tire) seat against the rim.
Key Point: As highlighted in the reference, "don't make the mistake of measuring the overall width... the wheel is actually measured from where the tire sits on each side."
Steps to Measure Wheel Width
Measuring your wheel's width requires a bit of precision. You can use a ruler or measuring tape.
- Locate the Bead Seats: These are the flat surfaces on the inside of the wheel's lip where the tire's bead presses against the metal.
- Measure the Inside Distance: Measure the straight-line distance across the wheel from the bead seat on one side to the bead seat directly opposite it on the other side.
- Note the Measurement: The resulting measurement is your wheel's width. This measurement is typically given in inches.
For example, the reference shows a wheel measured this way, confirming it "is a 7 in."
Why Not Measure Overall Width?
Measuring the overall width of the wheel, from the very outer edge of one lip to the outer edge of the opposite lip, includes the thickness of the rim flanges. This measurement is not the standard way wheel width is specified and will give you a larger number than the correct bead-seat-to-bead-seat measurement. Using the overall width for tire fitment will lead to incorrect results.
Understanding this specific measurement point ensures you select compatible tires that fit the wheel correctly and safely.
