Search results
Results From The WOW.Com Content Network
Prior to 1964, tires were all made to a 90% aspect ratio. Tire size was specified as the tire width in inches and the diameter in inches – for example, 6.50-15. [34] From 1965 to the early 1970s, tires were made to an 80% aspect ratio. Tire size was again specified by width in inches and diameter in inches.
Modern road tires have several measurements associated with their size as specified by tire codes like 225/70R14. The first number in the code (e.g., "225") represents the nominal tire width in millimeters. This is followed by the aspect ratio (e.g.,"70"), which is the height of the sidewall expressed as a percentage of the nominal tire width.
UTQG ratings (top) and tire code (bottom) on sidewall of Continental ContiProContact tire. Uniform Tire Quality Grading, commonly abbreviated as UTQG, is a set of standards for passenger car tires that measures a tire's treadwear, temperature resistance and traction. The UTQG was created by the National Highway Traffic Safety Administration in ...
NHTSA established the Uniform Tire Quality Grading System , is a system for comparing the performance of tires according to the Code of Federal Regulations 49 CFR 575.104; it requires labeling of tires for tread wear, traction, and temperature. The DOT Code is an alphanumeric character sequence molded into the sidewall of the tire and allows ...
Temperature: with both solid and pneumatic tires, rolling resistance has been found to decrease as temperature increases (within a range of temperatures: i.e. there is an upper limit to this effect) [59] [60] For a rise in temperature from 30 °C to 70 °C the rolling resistance decreased by 20-25%. [61]
Tire uniformity. Tire uniformity refers to the dynamic mechanical properties of pneumatic tires as strictly defined by a set of measurement standards and test conditions accepted by global tire and car makers. These standards include the parameters of radial force variation, lateral force variation, conicity, ply steer, radial run-out, lateral ...
Aspect ratio. The aspect ratio of a geometric shape is the ratio of its sizes in different dimensions. For example, the aspect ratio of a rectangle is the ratio of its longer side to its shorter side—the ratio of width to height, [ 1][ 2] when the rectangle is oriented as a "landscape". The aspect ratio is most often expressed as two integer ...
Cold inflation pressure is the inflation pressure of tires before a car is driven and the tires (tyres) warmed up. Recommended cold inflation pressure is displayed on the owner's manual and on the placard (or sticker) attached to the vehicle door edge, pillar, glovebox door or fuel filler flap. Most passenger cars are recommended to have a tire ...