Comparison of tire sizes 145/70 R12 and 135/70 R13
145/70R12
145
Tire width 
70
Profile height 
R12
Tire diameter 
627
RPM per km 145mm102mm508mm1595mm
145
70
12
135
70
13
| Parameters Sizes | Old | New | |||
|---|---|---|---|---|---|
| Diameter, mm | 508 | 519 | +11 (+2.2%) | ||
| Width, mm | 145 | 135 | -10 (-6.9%) | ||
| Circumference, mm | 1595 | 1631 | +36 (+2.3%) | ||
| Profile height, mm | 102 | 95 | -7 (-6.9%) | ||
| RPM per km | 627 | 613 | -14 (-2.2%) | ||
| Clearance change, mm | +6 | ||||
| Result: | The diameter differs by 2.2%. | ||||
| Speedometer reading (km/h) | |
|---|---|
| Real speed (km/h) | 102.3 |
| Difference (km/h) | 2.3 |
Sizes for comparison of tires 145/70 R12
R12
R13 +1
Sizes for comparison of tires 135/70 R13
R13
R12 -1
R14 +1