TYRE SIZE & SPEEDO ERROR
Compare any two tyre sizes. Diameter, ride height, speedo and odometer error, clearance needed, and what it does to your gearing. Metric (265/70R17), flotation (35x12.50R17) and plain diameter all work.
Speedometer error
Your speedo was calibrated for the stock tyre. With the new tyre fitted it reads:
| Speedo shows | You are actually doing | Error |
|---|
Same-diameter alternatives
Sizes within 1% of the new tyre's diameter — useful if your size is out of stock or expensive.
Diameters are unloaded geometric sizes from the printed markings — real rolling diameter is 1–3% smaller
under load and varies by brand, pressure and tread wear. Use it for comparison, not for legal speed claims.