Sounds like you either have a bad battery or a short somewhere.
Disconnect the battery leads and test between them with multimeter set to ohms....if you have any reading with the key set to "off" position, you have a short somewhere in the hot circuit to the switch, (hot wire to switch, or rectifier)
If not, have your battery tested.
If battery checks good, then the short is after the switch.
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1965 Honda CP77 — Ulsan Metro City, Rep. Korea
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