1. What is Revs Per Mile?

Revs per mile is a measurement that indicates how many times a wheel rotates when traveling one mile. This calculation is important for vehicle speedometer calibration, gear ratio selection, and tire size comparisons.

2. How Does the Calculator Work?

The calculator uses the following equation:

Where:

• \( Revs \) — Revolutions per mile
• \( Radius \) — Wheel radius in inches
• \( \pi \) — Mathematical constant (approximately 3.14159)
• 10080 — Conversion factor (1 mile = 63,360 inches, divided by 2π to account for circumference)

Explanation: The equation calculates how many full rotations (revolutions) a wheel makes to cover one mile based on its radius.

3. Importance of Revs Per Mile Calculation

Details: Knowing revs per mile is crucial for accurate speedometer readings, proper gear ratio selection, and when changing tire sizes to maintain vehicle performance and instrumentation accuracy.

4. Using the Calculator

Tips: Measure your wheel radius in inches (from center of wheel to ground with normal load) and enter the value. The radius must be greater than 0.

5. Frequently Asked Questions (FAQ)

Q1: How do I measure wheel radius accurately?
A: Measure from the center of the wheel hub to the ground with the vehicle at normal ride height and tire pressure.

Q2: Does tire pressure affect revs per mile?
A: Yes, underinflated tires will have a slightly smaller effective radius, increasing revs per mile.

Q3: Why is this important for speedometer accuracy?
A: Speedometers calculate speed based on wheel rotations. If revs per mile changes (like with different tire sizes), the speedometer will be inaccurate.

Q4: What's a typical revs per mile value?
A: For passenger cars, it's typically between 700-900 revs/mile, depending on wheel size.

Q5: Can I use diameter instead of radius?
A: Yes, but you'll need to adjust the formula to: Revs = 20160 / (Diameter × π)