LOCATIONSCONTACT US TIRES RETREAD SERVICES RESOURCES ABOUT ACTION TIRE Tire Definitions Other Resources Aspect Ratio (Section Height/Section Width) X 100 Deflection Free radius minus loaded radius. Free Radius The radius of the tire/wheel assembly that is not deflected under load. Loaded Radius Distance from wheel axis of rotation to supporting surface at a given load and stated inflation pressure. Loaded Section Height The loaded radius minus half of the nominal rim diameter. Distance from rim seat to outer tread surface of a loaded tire. Nominal Rim Diameter Diameter of rim seat supporting the tire bead. Examples: 13″, 15″ and 16.5″. Overall Width Maximum width in cross section of unloaded tire including protruding side ribs and decorations. Revolutions Per Mile Measured number of revolutions for a tire traveling one mile. This can vary with load and inflation. Rim Width Linear distance between rim flanges in contact with the tire. Rolling Circumference The linear distance traveled by a tire in one revolution. This can vary with load and inflation. Rolling circumference can be calculated as follows: 63,360 divided by revolutions per mile = rolling circumference in inches. Section Height Distance from rim seat to outer tread surface of unloaded tire. Section Width Linear distance between the outside sidewalls of an inflated tire without any load (exclusive of protruding side ribs and decorations). Tread Width The portion of the tread design which comes in contact with the road. Tire cutaway diagram Find a Location Our Services Our Tires 410 Lees Mill Road, Forest Park, GA 30297, (404) 767-3235 TIRES Shop by Brand ABOUT ACTION TIRE Overview Why Action Tire Contact Us Locations & Hours Satisfied Customers Careers Survey ATC Credit Application Payment RETREADS Retread location info SERVICES Services Overview Passenger & Light Truck Commercial Truck OTR & Utility Industrial & Farm Roadside Service Tire Fill Fleet Service RESOURCES Speed-Rating System Tire Rotation Tire Definitions UTQG Wheel Alignment When to Replace Tires Resources Air Pressure Basic Wheel Information Battery Tire Construction Read a Sidewall ACTION TIRE SURVEY We aim to satisfy our customers 100%. Help us better provide service and products to you. Take Survey ACTION TIRE APP Locate Action Tire Centers. Available on Google Play and App Store Download App MAKE A PAYMENT Conveniently pay an invoice online Make Payment ©2021 Action Tire Co., All Rights Reserved site credits