How to calculate tire outer diameter and circumference from tire size

　・In Japanese

Explains how to calculate the outer diameter and circumference of a tire from the tire size.

■How to read tire size

As below. Normally, when increasing the tire size, only the inner diameter of the tire is increased (inch up). Changing the outer diameter of the tires is not a good idea as it will change the vehicle speed displayed on the meter.

■How to calculate outer diameter and circumference

＜Calculate with specific values＞
Use the tire size specifications above.

List of related articles TOP MENU Automotive engineering ・Running resistance ・Vehicle acceleration ・Alternator ・Fuel injection amount ・IMEP vs BMEP ・MY, CY, FY ・Turning Radius ・Roll, Pitch, Yaw ・Torque and power ・Engine vs vehicle speed ・WLTP, WLTC ・OBD ・Tire size ・Failsafe, failproof ・Water,Buttock,Transverse Line ・Gears, splines