Lighter than Carbon...
The lightest possible way: wire race bearings with housing parts from the 3D printers are the lightest bearing assemblies of Franke.
Aluminum granulate is build up layer by layer to a geometric shape by using laser beams (laser sintering). Unlike traditional manufacturing with 3D-printing the internal geometry of the workpieces can be designed freely. Adapted to the load on the bearing the thickness of the material can be chosen in order to save material and thereby weight.
The manufacturing process also affects the production conditions: if necessary the 3D printer can produce the parts within a few hours.