Comparison of tire sizes 155/70 R12 and 165/55 R14
155/70R12
155
Tire width 
70
Profile height 
R12
Tire diameter 
610
RPM per km 155mm109mm522mm1639mm
155
70
12
165
55
14
| Parameters Sizes | Old | New | |||
|---|---|---|---|---|---|
| Diameter, mm | 522 | 537 | +15 (+2.9%) | ||
| Width, mm | 155 | 165 | +10 (+6.5%) | ||
| Circumference, mm | 1639 | 1687 | +48 (+2.9%) | ||
| Profile height, mm | 109 | 91 | -18 (-16.5%) | ||
| RPM per km | 610 | 593 | -17 (-2.8%) | ||
| Clearance change, mm | +8 | ||||
| Result: | The diameter differs by 2.9%. | ||||
| Speedometer reading (km/h) | |
|---|---|
| Real speed (km/h) | 102.9 |
| Difference (km/h) | 2.9 |
Sizes for comparison of tires 155/70 R12
R12
R13 +1
R14 +2
Sizes for comparison of tires 165/55 R14
R14
R13 -1
R15 +1
R12 -2
