Can’t turn your CDI-equipped Honda CX500’s engine off? Check that the black-wire-with-white-stripe is connected properly, and has continuity to the ignition switch. The wire should be near the pink and yellow wires going to the ignition coils, and looks like this (on the left):

This can sometimes be due to the CDI box being faulty. You can test for this by unplugging the black-with-white-stripe wire from the CDI box, starting the bike and then grounding the black-with-white-wire to the frame. Assuming you get a solid ground connection, the bike’s engine should stop. If it doesn’t with a good ground, your CDI box is faulty.