1. What is a Bike Speed Gear Ratio Calculator?

Definition: This calculator estimates bike speed based on pedaling cadence, gear ratio, and wheel circumference.

Purpose: It helps cyclists understand how different gear ratios affect their speed at various cadences.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( S \) — Speed (km/h)
• \( Cadence \) — Pedaling rate (revolutions per minute)
• \( GR \) — Gear ratio (chainring teeth ÷ cog teeth)
• \( WheelCirc \) — Wheel circumference (meters)

Explanation: The formula calculates how far the bike travels per minute based on pedaling rate and gear ratio, then converts to km/h.

3. Importance of Bike Speed Calculation

Details: Understanding this relationship helps cyclists select appropriate gears for target speeds and optimize pedaling efficiency.

4. Using the Calculator

Tips: Enter your cadence (typical 60-100 rpm), gear ratio (e.g., 50/12 = 4.17), and wheel circumference (standard road bike ~2.1m).

5. Frequently Asked Questions (FAQ)

Q1: What's a typical cadence?
A: Most cyclists maintain 80-100 rpm, with competitive riders often at 90-110 rpm.

Q2: How do I find my gear ratio?
A: Divide the number of teeth on your chainring by the number on your rear cog (e.g., 50/25 = 2.0).

Q3: How do I measure wheel circumference?
A: Roll your bike one wheel revolution and measure the distance, or use tire size charts.

Q4: Why multiply by 3.6 in the formula?
A: This converts meters per second to kilometers per hour (1 m/s = 3.6 km/h).

Q5: Does this account for resistance or hills?
A: No, this calculates theoretical speed. Actual speed will be lower due to air resistance, rolling resistance, and terrain.