The zeroth order kinetic energy is developed for the vibrating-internally rotating-rotating CH3OH molecule using the general theory of Guan and Quade for large amplitude internal motion-vibration-rotation interactions in molecules. The R and T transformations are applied, respectively, to separate internal rotation from the other vibrations and overall rotation from the other vibrations in zeroth order. All zeroth order kinetic energy coefficients are calculated from the geometry and atomic masses of the CH3OH molecule. The physical significance of the two transformations is discussed in detail. This paper reports the results of the first segment of the many segments necessary in the calculations for full solution of the problem. Copyright 1998 Academic Press.