The purpose of this recommended practice is to establish tire revolutions Per Mile (RPM) and Static Loaded Radius (SLR) values to be used for calculating off-road machine dimensions and performance. this recommended practice covers commonly used off-road tire sizes in tire type categories of E, G, and L in diagonal (bias) ply and radial ply constructions.
SAE J1544-1988 history
2011SAE J1544-2011 Revolutions per Mile and Static Loaded Radius for Off-Road tires
1988SAE J1544-1988 Revolutions per Mile and Static Loaded Radius for Off-Road Tires, Standard January 1988