Comparison of tire sizes 155/65 R14 and 185/55 R15
155/65R14
155
Tire width 
65
Profile height 
R14
Tire diameter 
571
RPM per km 155mm101mm557mm1750mm
155
65
14
185
55
15
| Parameters Sizes | Old | New | |||
|---|---|---|---|---|---|
| Diameter, mm | 557 | 585 | +28 (+5%) | ||
| Width, mm | 155 | 185 | +30 (+19.4%) | ||
| Circumference, mm | 1750 | 1836 | +86 (+4.9%) | ||
| Profile height, mm | 101 | 102 | +1 (+1%) | ||
| RPM per km | 571 | 545 | -26 (-4.6%) | ||
| Clearance change, mm | +14 | ||||
| Result: | The diameter differs by 5%. | ||||
| Speedometer reading (km/h) | |
|---|---|
| Real speed (km/h) | 104.9 |
| Difference (km/h) | 4.9 |
Sizes for comparison of tires 155/65 R14
R14
R13 -1
R15 +1
R16 +2
Sizes for comparison of tires 185/55 R15
R15
R14 -1
R16 +1
R13 -2
R17 +2