1. What is a Bike Gear Ratio Calculator?

Definition: This calculator determines the gear ratio (GR) of a bicycle based on the number of teeth on the chainring and cog.

Purpose: It helps cyclists understand their gearing setup and compare different gear combinations for optimal performance.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( GR \) — Gear ratio (unitless)
• \( Chainring \) — Number of teeth on front chainring
• \( Cog \) — Number of teeth on rear cog

Explanation: The gear ratio shows how many times the rear wheel turns for each pedal revolution. Higher ratios mean more speed per pedal stroke but require more effort.

3. Importance of Gear Ratio Calculation

Details: Proper gear ratio selection affects pedaling efficiency, speed potential, and climbing ability. It helps cyclists choose appropriate gearing for different terrains.

4. Using the Calculator

Tips: Enter the number of teeth on your chainring and cog (both must be ≥1). Typical chainrings range from 30-55 teeth, while cogs range from 10-36 teeth.

5. Frequently Asked Questions (FAQ)

Q1: What's a good gear ratio for climbing hills?
A: Lower ratios (1.0-2.0) are better for climbing as they require less effort per pedal stroke.

Q2: What's a good gear ratio for flat terrain?
A: Higher ratios (3.0-5.0) are better for flats as they allow higher speeds with each pedal stroke.

Q3: How does wheel size affect gearing?
A: This calculator shows gear ratio only. For gear inches (which includes wheel size), multiply the ratio by wheel diameter in inches.

Q4: What's the difference between gear ratio and gear inches?
A: Gear ratio is chainring/cog, while gear inches multiplies this by wheel diameter to show equivalent wheel size of an old penny-farthing bike.

Q5: How do I choose gears for my bike?
A: Consider your fitness level, terrain, and riding style. More chainring teeth and fewer cog teeth create higher (harder) gears.