Improved magnetic rotor assemblies are provided. In one embodiment, a magnetic rotor assembly includes two or more rotor disks. The rotor disks may each contain corresponding sets of permanent magnets, which may be circumferentially disposed around the disks. The disks may then positioned near one another such that the disks are magnetically coupled. In certain instances, the N-poles of the permanent magnets may face one another. In other instances, the S-poles of the permanent magnets may face one another.