1. What is a Bike Gearing Speed Calculator?

Definition: This calculator estimates bicycle speed based on pedaling cadence (RPM), tire diameter, and gear ratio.

Purpose: It helps cyclists understand how different gear combinations and cadence affect their speed.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( S \) — Speed (miles per hour)
• \( RPM \) — Pedal revolutions per minute
• \( TD \) — Tire diameter (inches)
• \( GR \) — Gear ratio (chainring teeth ÷ cog teeth)

Explanation: The formula converts rotational motion to linear speed, accounting for wheel size and gearing.

3. Importance of Gear Ratio Calculation

Details: Understanding gear ratios helps cyclists select appropriate gears for different terrain and maintain efficient cadence.

4. Using the Calculator

Tips: Enter your cadence (RPM), tire diameter in inches, and gear ratio. Typical values are pre-filled (90 RPM, 27" tires, 3.73 gear ratio).

5. Frequently Asked Questions (FAQ)

Q1: What's a typical cycling cadence (RPM)?
A: Most cyclists maintain 80-100 RPM, with 90 RPM being a common target for efficient pedaling.

Q2: How do I measure my tire diameter?
A: Check the sidewall markings (e.g., 700x25c ≈ 27", 26" MTB tires ≈ 26"). For accuracy, measure the actual rolling diameter.

Q3: How do I calculate gear ratio?
A: Divide the number of teeth on your chainring by the number of teeth on your rear cog (e.g., 52/14 = 3.71).

Q4: Why does tire diameter affect speed?
A: Larger tires cover more ground per revolution, increasing speed at the same RPM.

Q5: What's the 1056 constant in the formula?
A: This converts inches per minute to miles per hour (12 inches/foot × 5280 feet/mile ÷ 60 minutes/hour).