1. What is Wheel RPM?

Wheel RPM (Revolutions Per Minute) measures how many full rotations a wheel makes in one minute. It's an important parameter in vehicle dynamics, performance tuning, and gear ratio calculations.

2. How Does the Calculator Work?

The calculator uses the Wheel RPM formula:

Where:

• 336 — Constant that combines unit conversions (5280 ft/mile × 12 in/ft ÷ 60 min/hour)
• Speed — Vehicle speed in miles per hour (mph)
• Tire Diameter — Diameter of the tire in inches

Explanation: The formula converts vehicle speed to the rotational speed of the wheels based on tire size.

3. Importance of Wheel RPM Calculation

Details: Knowing wheel RPM helps in gear ratio selection, performance tuning, verifying speedometer accuracy, and understanding vehicle dynamics at different speeds.

4. Using the Calculator

Tips: Enter speed in mph and tire diameter in inches. Both values must be positive numbers. For accurate results, measure tire diameter when properly inflated and under load.

5. Frequently Asked Questions (FAQ)

Q1: Why is the constant 336 used in the formula?
A: It combines several conversion factors: 5280 feet per mile, 12 inches per foot, and 60 minutes per hour (5280 × 12 ÷ 60 = 336).

Q2: How do I measure my tire diameter?
A: Measure from the ground to the top of the tire (while loaded) and multiply by 2. Alternatively, use the tire size markings to calculate theoretical diameter.

Q3: Does wheel RPM change with different gear ratios?
A: No, wheel RPM is determined by vehicle speed and tire size. Gear ratios affect engine RPM at a given wheel RPM.

Q4: What's a typical wheel RPM range?
A: At highway speeds (60-70 mph), typical wheel RPM ranges from 700-900 RPM depending on tire size.

Q5: Can I use this for metric units?
A: The formula is designed for mph and inches. For km/h and mm, you would need a different constant (approximately 1046 instead of 336).