Comparison of tire sizes 285/65 R18 and 275/60 R18
285/65R18
285
Tire width 
65
Profile height 
R18
Tire diameter 
385
RPM per km 285mm185mm828mm2600mm
285
65
18
275
60
18
| Parameters Sizes | Old | New | |||
|---|---|---|---|---|---|
| Diameter, mm | 828 | 787 | -41 (-5%) | ||
| Width, mm | 285 | 275 | -10 (-3.5%) | ||
| Circumference, mm | 2600 | 2473 | -127 (-4.9%) | ||
| Profile height, mm | 185 | 165 | -20 (-10.8%) | ||
| RPM per km | 385 | 404 | +19 (+4.9%) | ||
| Clearance change, mm | -21 | ||||
| Result: | The diameter differs by -5%. | ||||
| Speedometer reading (km/h) | |
|---|---|
| Real speed (km/h) | 95.1 |
| Difference (km/h) | -4.9 |
Sizes for comparison of tires 285/65 R18
R18
R17 -1
R16 -2
R20 +2
Sizes for comparison of tires 275/60 R18
R18
R17 -1
R19 +1
R16 -2
R20 +2