ReadyCalculator

Gear Ratio Speed

speed = (RPM / ratio) × πD / 60

Gearbox × final drive

How to Use This Calculator

Enter engine RPM, overall gear ratio (gear × final drive), and tire diameter. The calculator outputs linear speed.

Formula

v = (RPM/ratio) × πD / 60

Frequently Asked Questions

What if I have tire width/aspect/rim?

Convert to effective diameter using manufacturer data or compute rolling circumference; enter the diameter here.