Tires being flexible products are affected by many variables, so tire manufacturers use a standard method of measurement. The results of these measurements are the rounded off numbers molded on the tires. In posting these dimensions tires are mounted on what is called the “Design Rim”. The Design Rim is the rim that has been calculated to be the optimum or best all-around rim for a given tire. The tire to be measured is placed on the design rim, inflated to the maximum pressure shown on the sidewall of the tire then laid flat for 24 hours at room temperature. Then the air pressure is r