Is that a HUB with a key cylinder in it?
No, Pete. It's a keyed switch(auto parts store ignition switch) in a pair of plastic pipe caps glued together, back to back. I've used the same keyed switch set-up in plastic pipe caps on all 7 bikes I've built. Just drill holes in the ends and mount the switch in one end and a smaller hole in the other for the wires before you glue it. It works fine.
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