Tyre Size Calculator Comparison

Delta Percentage Formula:

\[ \Delta\% = \frac{New - Old}{Old} \times 100 \]

Delta Percentage (%):

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1. What is a Tyre Size Calculator Comparison?

Definition: This calculator compares two tyre sizes and calculates the percentage difference (delta) between them.

Purpose: It helps vehicle owners and mechanics understand how much a new tyre size differs from the original specification.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ \Delta\% = \frac{New - Old}{Old} \times 100 \]

Where:

\( \Delta\% \) — Percentage difference between tyre sizes
\( New \) — Diameter or width of new tyre (mm)
\( Old \) — Diameter or width of original tyre (mm)

Explanation: The formula calculates how much larger or smaller the new tyre is compared to the original, expressed as a percentage.

3. Importance of Tyre Size Comparison

Details: Proper tyre sizing affects speedometer accuracy, gearing, clearance, and vehicle handling. Significant differences may require modifications.

4. Using the Calculator

Tips: Enter the original tyre size and new tyre size in millimeters. Both values must be > 0. The result shows the percentage difference.

5. Frequently Asked Questions (FAQ)

Q1: What's considered an acceptable delta percentage?
A: Generally, up to ±3% is acceptable for most vehicles without major modifications.

Q2: Should I measure overall diameter or just width?
A: For most comparisons, overall diameter is most important as it affects gearing and speedometer accuracy.

Q3: What if I get a negative percentage?
A: A negative result means the new tyre is smaller than the original.

Q4: How does this affect my speedometer?
A: A positive delta means your actual speed is higher than shown, negative means lower than shown.

Q5: Where can I find my tyre size specifications?
A: Check the sidewall of your tyre or your vehicle's manual for original specifications.