Comparison of tire sizes 245/40 R18 and 285/40 R18
245/40R18
245
Tire width 
40
Profile height 
R18
Tire diameter 
487
RPM per km 245mm98mm653mm2052mm
245
40
18
285
40
18
| Parameters Sizes | Old | New | |||
|---|---|---|---|---|---|
| Diameter, mm | 653 | 685 | +32 (+4.9%) | ||
| Width, mm | 245 | 285 | +40 (+16.3%) | ||
| Circumference, mm | 2052 | 2153 | +101 (+4.9%) | ||
| Profile height, mm | 98 | 114 | +16 (+16.3%) | ||
| RPM per km | 487 | 465 | -22 (-4.5%) | ||
| Clearance change, mm | +16 | ||||
| Result: | The diameter differs by 4.9%. | ||||
| Speedometer reading (km/h) | |
|---|---|
| Real speed (km/h) | 104.9 |
| Difference (km/h) | 4.9 |
Sizes for comparison of tires 245/40 R18
R18
R17 -1
R19 +1
R16 -2
R20 +2
Sizes for comparison of tires 285/40 R18
R18
R17 -1
R19 +1
R16 -2
R20 +2
