Comparison of tire sizes 155/70 R12 and 135/70 R13

155/70R12
155 Tire width
70 Profile height
R12 Tire diameter
610 RPM per km
155mm109mm522mm1639mm
155
70
12
135
70
13
Parameters Sizes Old New
Diameter, mm522519-3 (-0.6%)
Width, mm155135-20 (-12.9%)
Circumference, mm16391631-8 (-0.5%)
Profile height, mm10995-14 (-12.8%)
RPM per km610613+3 (+0.5%)
Clearance change, mm-2
Result:
The diameter differs by -0.6%.
Speedometer reading (km/h)
Real speed (km/h)99.5
Difference (km/h)-0.5

Sizes for comparison of tires 155/70 R12

R12
R13 +1
R14 +2

Sizes for comparison of tires 135/70 R13

R13
R12 -1
R14 +1