Frequency-adaptive Lumped Mass Stick (LMS) method has been proposed recently to present the dynamic responses of a structure by a stick model which has identical frequencies to the original structure. The masses of the LMS model are obtained by an iterative method following a sequence of equations, where the masses always converge to certain values. Those values are solutions of a nonlinear equations system as will be shown in this study. This paper also investigates the significance of masses locations on the dynamic responses of the LMS models.