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Bike Gear Ratio Speed Calculator

Speed Formula:

\[ \text{Speed} = \frac{\text{Cadence} \times \frac{\text{Chainring}}{\text{Cog}} \times \text{Wheel Circumference}}{60} \]

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1. What is a Bike Gear Ratio Speed Calculator?

Definition: This calculator estimates cycling speed based on pedaling cadence, gear ratio (chainring/cog), and wheel circumference.

Purpose: Helps cyclists understand how different gear combinations affect their speed at various cadences.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ \text{Speed} = \frac{\text{Cadence} \times \frac{\text{Chainring}}{\text{Cog}} \times \text{Wheel Circumference}}{60} \]

Where:

Explanation: The gear ratio (chainring/cog) determines how many wheel revolutions occur per pedal revolution, which when multiplied by cadence and wheel circumference gives speed.

3. Importance of Gear Ratio Calculations

Details: Understanding gear ratios helps cyclists select appropriate gears for terrain, maintain efficient cadence, and predict speed performance.

4. Using the Calculator

Tips:

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this calculator?
A: It provides theoretical speed assuming no wheel slip and perfect conditions. Actual speed may vary due to terrain, wind, and riding position.

Q2: What's a good cadence for cycling?
A: Most efficient cadence is typically 80-100 rpm, though this varies by rider.

Q3: How do I measure wheel circumference?
A: Measure from ground to axle, double for diameter, then multiply by π (3.1416). Or roll bike one revolution and measure distance.

Q4: Why does gear ratio matter?
A: Higher ratios (big chainring/small cog) give more speed per pedal stroke but require more effort. Lower ratios are easier for climbing.

Q5: Can I use this for different bike types?
A: Yes, just adjust the wheel circumference and typical gear sizes for road, mountain, or hybrid bikes.

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