1. What is a Bicycle Tire Size Conversion Calculator?

Definition: This calculator converts traditional bicycle tire sizes (in inches) to the ETRTO (European Tire and Rim Technical Organization) standard in millimeters.

Purpose: It helps cyclists and mechanics determine compatible tire sizes when switching between different measurement systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( ETRTO \) — European standard tire size (millimeters)
• \( diameter \) — Traditional tire diameter (inches)
• \( bead \) — Bead seat diameter (inches, typically 0.2")

Explanation: The formula converts inches to millimeters and accounts for the tire bead that sits in the rim.

3. Importance of Tire Size Conversion

Details: Proper tire size matching ensures safe riding, proper clearance, and prevents damage to rims or frames.

4. Using the Calculator

Tips: Enter the tire diameter in inches and bead seat diameter (default 0.2 inches). The calculator will provide the ETRTO equivalent in millimeters.

5. Frequently Asked Questions (FAQ)

Q1: What is ETRTO?
A: ETRTO is the European standard for bicycle tire sizing that specifies the exact width and diameter in millimeters.

Q2: Why convert to ETRTO?
A: ETRTO provides more precise measurements than traditional sizing, ensuring better compatibility between tires and rims.

Q3: What's a typical bead seat diameter?
A: Most tires have a bead seat diameter of about 0.2 inches, but this can vary slightly between tire types.

Q4: How accurate is this conversion?
A: This provides an approximate conversion. Always check manufacturer specifications for exact measurements.

Q5: Can I use this for all bicycle tires?
A: This works best for standard bicycle tires. Specialty tires (like fat bike tires) may require different calculations.