+4.93%Borderline — noticeable speedometer/odometer error
Speedometer error
With a speedometer calibrated to 235/55R17, fitting 225/65R17 makes it read as follows:
| Speedo shows | True speed | Speedo shows | True speed |
|---|---|---|---|
| 40 km/h | 42.0 km/h | 25 mph | 26 mph |
| 60 km/h | 63.0 km/h | 37 mph | 39 mph |
| 80 km/h | 83.9 km/h | 50 mph | 52 mph |
| 100 km/h | 104.9 km/h | 62 mph | 65 mph |
| 120 km/h | 125.9 km/h | 75 mph | 78 mph |
Full comparison
235/55R17
Overall diameter690.3 mm · 27.18 in
Section width235 mm · 9.25 in
Sidewall height129.3 mm · 5.09 in
Circumference2168.6 mm · 85.4 in
Revolutions per mile742
Revolutions per km461
225/65R17
Overall diameter724.3 mm · 28.52 in
Section width225 mm · 8.86 in
Sidewall height146.3 mm · 5.76 in
Circumference2275.5 mm · 89.6 in
Revolutions per mile707
Revolutions per km439
+4.93%Borderline — noticeable speedometer/odometer error
Original
Overall diameter690.3 mm · 27.18 in
Sidewall height129.3 mm
Circumference2,168.6 mm
Revolutions / mile742.1
New
Overall diameter724.3 mm · 28.52 in
Sidewall height146.3 mm
Circumference2,275.5 mm
Revolutions / mile707.3
Speedometer & odometer error
The new tire changes overall diameter by +4.93%. 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 | 42 km/h | 25 mph | 26 mph |
| 60 km/h | 63 km/h | 37 mph | 39 mph |
| 80 km/h | 83.9 km/h | 50 mph | 52 mph |
| 100 km/h | 104.9 km/h | 62 mph | 65 mph |
| 120 km/h | 125.9 km/h | 75 mph | 78 mph |
See individual specs: 235/55R17 · 225/65R17. A change this size can affect ABS/speed calibration — see wheel-speed codes if a light appears.