It depends on what do you want to observe. If you want to observe only the dynamic motion, then use ANSYS rigid dynamics module. But if you want to observe stress distribution comming from external forces, then use ANSYS LS-Dyna or ANSYS structural explicit. In other cases you can also create a joint to avoid the creation of many geometrical details. But if you want something more advanced, the you can use the Design life analysis to estimate durability.

Hi,

For bearings durabilty and life of the bearings is more important so N Code design life is the best tool to simuate bearings; in that you also check the life and durability of the bearings

Good Wishes

Another good tool for simulating bearing is Transmission3D that uses an hybrid analitical-FEM approach.

Franco