I'm afraid that is one of those "How long is a piece of string?" questions. The battery may well be cattled after 6 years, but
they don't normally go from working fine to totally dead.
How long since the bike was last used?
Did you leave the parking lights on accidentally? Don't know about the 06 bikes but on the current models you only have to press the LH indicator switch for a few seconds after switching off the ignition to activate the parking lights - they will totally drain the battery in a matter of hours.
Have you tried charging the battery?
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