Flywheels are a possible solution to support electromobility and grid stability in light of the challenges posed by renewable energy sources. In a flywheel, energy is stored in a fast-rotating mass, which is magnetically levitated under normal operation. In case of malfunction of the magnetic bearings, mechanical fallback bearings – the so-called touch-down bearings – prevent system destruction. To increase energy density, modern flywheels are built with an outer rotor concept. This however prevents the use of conventional touch-down bearings, so a planetary design is applied. Furthermore, the rotor surface contacting the touch-down bearings must have small gaps to reduce material stress. In addition, material adhesion leads to bumps on the rotor surface. Up to now, it has not been investigated how this unevenness influences the loads on the touch-down bearings during drop-downs. Therefore, in this paper, a simulation model and study are shown to investigate the influence of gaps and bumps on the rotor surface. To analyze the results, the two severity indicators maximum force and bearing service life are used. It is shown that the influence of the gaps on these indicators is negligible. However, bumps can lead to an increase in the maximum normal force of up to 50% while the bearing service life decreases by 50%.