Disc brake hubs

The spindles and hubs are different. I suspect the bearings are different too, but rockauto would tell you. I never heard of anyone doing it, but perhaps you could find bearings which will fit both the disk spindle and drum hub. Tapered roller bearings are actually sold as 2 different parts - cone and race. Some are packaged as a kit and labelled "SET1", "SET2", etc (Timken PN's). If you can find a cone PN w/ proper ID for the spindle and a matching race PN w/ proper OD for the hub, it "should work". Not that hard since bearings come in standard metric sizes (thanks to Germans). Then you would need to figure how to attach the rotor to the hub. The K-H rotor sits behind the disk hub's flange. But, you could install it on the outside of a drum hub (as all modern rotors do).

I test-fitted this for a crazy idea, using a 10" drum hub. My K-H rotors would need a little machining on the inside to get a flat surface to match the hub's OD. The center hole of the rotor was also larger. and the bolts are bigger OD. The center hole issue could be fixed with a nylon "hub spacer" (ebay) if you can find the right size. All above could be fixed w/ a custom adapter (someday if I get my CNC going). Then would the rotor sit at an axial location to match the K-H caliper? In my case, I wasn't concerned since idea was to mount a Wilwood caliper on a custom bracket off the 10" drum spindle, similar to Wilwood and Scarebird kits.