We presents an extended theoretical study on the bouncing vibration of a single-degree-of-freedom contact slider model and the complete contact condition for high density contact magnetic recording. The relationship between bounce height and waviness frequency and the role of the top contact point necessary for stable bouncing vibration are discussed. Since the dynamic contact force increases up to ten times the static head load even when the bounce height is only one nanometer, complete contact sliding without separation is indispensable for reliable contact recording. The complete tracking conditions onto the disk surface under ten nanometer bounce height disturbances are calculated for various design parameter values, including the phase of the waviness. It is also shown that a collision model can predict almost the same complete tracking boundaries as the elastic contact model.