The influence of triaxial deformation γ on the purely collective form of wobbling motion in even–even nuclei is discussed based on the triaxial rotor model. It is found that the harmonic approximation is realized well when the value γ = 30° is adopted for the properties of energy spectra and electric quadrupole transition probabilities, while this approximation gets worse when γ gradually deviates from 30°. Recent data from a Coulomb excitation experiment, namely and for 110Ru, are studied and might be suggested as the bandhead of the wobbling bands. In addition, two types of angular momentum geometries for wobbling motion, stemming from different γ values, are exhibited by the azimuthal plots.