Comparison of tire sizes 275/55 R20 and 255/55 R20
275/55R20
275
Tire width 
55
Profile height 
R20
Tire diameter 
393
RPM per km 275mm151mm811mm2546mm
275
55
20
255
55
20
| Parameters Sizes | Old | New | |||
|---|---|---|---|---|---|
| Diameter, mm | 811 | 789 | -22 (-2.7%) | ||
| Width, mm | 275 | 255 | -20 (-7.3%) | ||
| Circumference, mm | 2546 | 2477 | -69 (-2.7%) | ||
| Profile height, mm | 151 | 140 | -11 (-7.3%) | ||
| RPM per km | 393 | 404 | +11 (+2.8%) | ||
| Clearance change, mm | -11 | ||||
| Result: | The diameter differs by -2.7%. | ||||
| Speedometer reading (km/h) | |
|---|---|
| Real speed (km/h) | 97.3 |
| Difference (km/h) | -2.7 |
Sizes for comparison of tires 275/55 R20
R20
R19 -1
R21 +1
R18 -2
R22 +2
Sizes for comparison of tires 255/55 R20
R20
R19 -1
R21 +1
R18 -2
R22 +2
