Affiliate disclosure: This post may contain affiliate links. If you buy through a link on this page, MOTOZMO may earn a small commission at no extra cost to you. It helps keep our guides free. How we test and choose products.
Comparing two tire sizes? Enter both sidewall sizes and see the real diameter change, what it does to your speedometer, and what it does to your gearing.
Your tire sizes
Current tire
New tire
Motozmo Tire Size Comparison Calculator – motozmo.com
Your result
How it works: overall diameter is the rim size plus twice the sidewall height, and sidewall height is the width multiplied by the aspect ratio. The speedometer figure assumes the bike was accurate on the current tire; many bikes read a few percent high from the factory, which stacks with this change.
Check clearance, load rating, and rim width with the tire maker and your manual before fitting a different size. A diameter change also changes ground clearance and handling, so a size that fits on paper is not automatically the right size for your bike.
Related Guides
When to Replace Motorcycle Tires — when a tire is due, before comparing sizes.
Checking Motorcycle Tires — how to inspect tires before deciding on a change.
More Rider Tools
Sprocket and Gear Ratio Calculator — what a sprocket swap does to your gearing, rpm and top speed.
Fuel Cost and MPG Calculator — your real MPG, trip cost, cost per mile and true tank range.
Wind Chill Calculator — what the temperature really feels like at riding speed.