This paper presents the implementation of the Taguchi method for a retrofit design of a line-start permanent magnet motor. To evaluate the viability of the method, the optimum designs obtained from both the Taguchi and a traditional optimization methods are compared. This outlines the respective advantages and disadvantages of both methods. It shows that the Taguchi method is an efficient and robust design approach and possesses some unique advantages compared to conventional design methods. A design sensitivity investigation regarding the variances of certain parameters, due to manufacturing tolerances and material properties discrepancies, is also presented using the Taguchi method. From this investigation insight into the contribution of each parameter towards machine performance is gained for the steady-state performance of an embedded radial flux line-start permanent magnet motor.