freeze
06-24-2009, 03:36 PM
Metric really messes me up since I'm used to something like 35x12.5R15. With these metric tires it's all messed up... at least for me.
Here's another excerpt from pirate on how to calculate your metric tire.
The Metric system first appeared in the 1970’s and was called the Euro-Metric system because it began in Europe. It is the first system that tells us virtually all we need to know, though some information must be calculated from the figures given.
Example:
235/75R15
235 is the section width in mm
75 is the Aspect Ratio in %
R denotes radial construction (D = (diagonal) bias ply construction; B = belted bias construction)
15 is the rim diameter in inches
To calculate the complete dimensions:
First change section width to inches by dividing the mm by 25.4
235/25.4 = 9.25” wide
Then calculate the OD in inches by multiplying the Section Width by the Aspect Ratio (to get the height of the sidewall), doubling it, and adding the diameter of the rim
OD = ((9.25*.75)*2)+15 = 28.87 ~ 29”
Therefore a 235/75/R15 is a 29” x 9.25” R15T
Here's another excerpt from pirate on how to calculate your metric tire.
The Metric system first appeared in the 1970’s and was called the Euro-Metric system because it began in Europe. It is the first system that tells us virtually all we need to know, though some information must be calculated from the figures given.
Example:
235/75R15
235 is the section width in mm
75 is the Aspect Ratio in %
R denotes radial construction (D = (diagonal) bias ply construction; B = belted bias construction)
15 is the rim diameter in inches
To calculate the complete dimensions:
First change section width to inches by dividing the mm by 25.4
235/25.4 = 9.25” wide
Then calculate the OD in inches by multiplying the Section Width by the Aspect Ratio (to get the height of the sidewall), doubling it, and adding the diameter of the rim
OD = ((9.25*.75)*2)+15 = 28.87 ~ 29”
Therefore a 235/75/R15 is a 29” x 9.25” R15T