1. What is Tire Diameter?

Tire diameter is the overall height of the tire when mounted and inflated. It's calculated by adding the rim diameter to twice the sidewall height.

2. How Does the Calculator Work?

The calculator uses the tire diameter formula:

Where:

• \( Rim \) — Diameter of the wheel rim in inches
• \( Sidewall \) — Height of the tire sidewall in inches

Explanation: The sidewall height is multiplied by 2 because it appears on both sides of the rim (top and bottom).

3. Importance of Tire Size Calculation

Details: Correct tire diameter is crucial for proper vehicle operation, speedometer accuracy, clearance issues, and maintaining the correct gear ratios.

4. Using the Calculator

Tips: Enter rim diameter and sidewall height in inches. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: Where can I find rim and sidewall measurements?
A: Rim diameter is usually stamped on the wheel. Sidewall height can be calculated from tire size markings (aspect ratio × width / 100).

Q2: How does tire diameter affect my vehicle?
A: Larger diameters may affect speedometer readings, acceleration, and clearance. Smaller diameters may reduce ground clearance.

Q3: What's a typical sidewall height?
A: Passenger cars typically have 3-5 inches, while trucks/SUVs may have 5-8 inches or more.

Q4: Can I use this for bicycle tires?
A: Yes, the same formula applies to bicycle tires, though measurements are typically in inches for both rim and tire.

Q5: How precise does this need to be?
A: For most applications, ±0.5 inch is acceptable, but precision matters more for speed-sensitive applications.