165/70R14 vs 185/60R14
Switching from 165/70R14 to 185/60R14 decreases the overall diameter by 9.0 mm (1.5%). That is within the usual ±3% guideline.
| 165/70R14 | 185/60R14 | Difference (mm / revs) | |
|---|---|---|---|
| Section width | 165 mm | 185 mm | +20.0 |
| Sidewall height | 115.5 mm | 111.0 mm | -4.5 |
| Rim diameter | 355.6 mm | 355.6 mm | +0.0 |
| Overall diameter | 586.6 mm | 577.6 mm | -9.0 |
| Circumference | 1,842.9 mm | 1,814.6 mm | -28.3 |
| Revolutions | 543 per km | 551 per km | +8.0 |
Speedometer effect
With 185/60R14 fitted on a car calibrated for 165/70R14, the real speed when the speedometer shows:
| Speedometer shows | Actual speed |
|---|---|
| 50 km/h | 49.2 km/h |
| 80 km/h | 78.8 km/h |
| 100 km/h | 98.5 km/h |
| 120 km/h | 118.2 km/h |
Smaller tires make the speedometer read higher than the actual speed. Most speedometers also read slightly high from the factory.
Before you change size
- Check the sizes approved for your vehicle on the door-jamb placard or in the owner's manual.
- Check clearance to suspension, brakes and arches at full lock and full compression.
- Match or exceed the original load index and speed rating.
- Wider tires need an appropriate rim width; a 185 mm tire has a manufacturer-specified rim width range.
165/70R14 dimensions · 185/60R14 dimensions · Open in calculator