-1.05%Safe swap — speedometer error is minor
Speedometer error
With a speedometer calibrated to 185/65R15, fitting 195/60R15 makes it read as follows:
| Speedo shows | True speed | Speedo shows | True speed |
|---|---|---|---|
| 40 km/h | 39.6 km/h | 25 mph | 25 mph |
| 60 km/h | 59.4 km/h | 37 mph | 37 mph |
| 80 km/h | 79.2 km/h | 50 mph | 49 mph |
| 100 km/h | 99.0 km/h | 62 mph | 61 mph |
| 120 km/h | 118.7 km/h | 75 mph | 74 mph |
Full comparison
185/65R15
Overall diameter621.5 mm · 24.47 in
Section width185 mm · 7.28 in
Sidewall height120.3 mm · 4.73 in
Circumference1952.5 mm · 76.9 in
Revolutions per mile824
Revolutions per km512
195/60R15
Overall diameter615.0 mm · 24.21 in
Section width195 mm · 7.68 in
Sidewall height117.0 mm · 4.61 in
Circumference1932.1 mm · 76.1 in
Revolutions per mile833
Revolutions per km518
-1.05%Safe swap — speedometer error is minor
Original
Overall diameter621.5 mm · 24.47 in
Sidewall height120.3 mm
Circumference1,952.5 mm
Revolutions / mile824.2
New
Overall diameter615 mm · 24.21 in
Sidewall height117 mm
Circumference1,932.1 mm
Revolutions / mile833
Speedometer & odometer error
The new tire changes overall diameter by -1.05%. With a speedometer calibrated to the original tire, that same percentage is how far the speedometer and odometer read off — a taller tire means your true speed is higher than indicated and the odometer under-counts distance.
| Speedo shows | True speed | Speedo shows | True speed |
|---|---|---|---|
| 40 km/h | 39.6 km/h | 25 mph | 25 mph |
| 60 km/h | 59.4 km/h | 37 mph | 37 mph |
| 80 km/h | 79.2 km/h | 50 mph | 49 mph |
| 100 km/h | 99 km/h | 62 mph | 61 mph |
| 120 km/h | 118.7 km/h | 75 mph | 74 mph |
See individual specs: 185/65R15 · 195/60R15. A change this size can affect ABS/speed calibration — see wheel-speed codes if a light appears.