Power-train arrangements, such as a two-rotor system with one overhang, have a wide spectrum of industrial applications, from a workbench grinder to compressor-turbine unit. Based on a typical dimension, flexural critical speeds both in the forward and backward whirl are calculated by a commercial software package. These critical speeds are further analyzed by varying the shaft overhung, rotor inertia and gyroscopic effect. Parametric analysis would enable designers to make a trade-off study and obtain a satisfactory operation. In extreme conditions, results obtained have been verified with available analytical solutions.