Samenvatting
An analysis is made to determine the optimum speed for heavy motor vehicle, and it is found that for normal South Africa conditions this speed is lower than 80 km/h. The maximum speed limit of 80 km/h, therefore, holds no adversities for the economics of heavy road transportation. It, in fact, has a beneficial effect, as the authorities and motoring public help the commercial transporter by ensuring that the heavy vehicles do not travel above the maximum speed.