Comparison of tire sizes 145/70 R12 and 155/65 R13
145/70R12
145
Tire width 
70
Profile height 
R12
Tire diameter 
627
RPM per km 145mm102mm508mm1595mm
145
70
12
155
65
13
| Parameters Sizes | Old | New | |||
|---|---|---|---|---|---|
| Diameter, mm | 508 | 532 | +24 (+4.7%) | ||
| Width, mm | 145 | 155 | +10 (+6.9%) | ||
| Circumference, mm | 1595 | 1670 | +75 (+4.7%) | ||
| Profile height, mm | 102 | 101 | -1 (-1%) | ||
| RPM per km | 627 | 599 | -28 (-4.5%) | ||
| Clearance change, mm | +12 | ||||
| Result: | The diameter differs by 4.7%. | ||||
| Speedometer reading (km/h) | |
|---|---|
| Real speed (km/h) | 104.7 |
| Difference (km/h) | 4.7 |
Sizes for comparison of tires 145/70 R12
R12
R13 +1
Sizes for comparison of tires 155/65 R13
R13
R12 -1
R14 +1