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One of the effective criteria for assessing the stability of the curved motion of wheeled tractors and machine-tractor units assembled on their basis is the x-ordinate and y-abscissa of the kinematic center's turning trajectory. Currently, equations based on the formula for determining the theoretical minimum radius (TMR) of a true turn are used to analytically calculate the x- and ycoordinates of a wheeled tractor's unsteady turn. It has been established that for the actual turn of a wheeled vehicle, implemented by a rear-mounted four-link steering trapezoid, the calculated dependence for finding the TMR of the actual turn will not be identical to the dependence for a true turn. This article derives equations for determining the coordinates of the theoretical trajectory of the actual turn and presents the results of calculations using these equations, pertaining to the Belarus-1221.2 universal rowcrop tractor. A discrepancy between the values of the main kinematic characteristics of the correct and actual transient turns was revealed. The turn abscissas differ by 4-80%, depending on the values of the steering wheel turning angles, and the TMR of the turn – by 7.5-21.3%. With an increase in the forward speed of the tractor from 1.86 m/s to 2.556 m/s, the values of the abscissa x increase for both the correct and actual turns by 43.71...47.27%, and the ordinate y – by 21.5...27.17%. In this case, the instantaneous theoretical turning radius does not change. Thus, the necessity of using equations derived from the formula for determining the TMR of the actual turn for calculating the coordinates of the trajectory of the wheeled vehicle is proven. The conducted verification of the adequacy of the obtained equations yielded complete convergence of the results.