First get hold of a volt meeter to see if the bike is charging the battery if its not charging then its likley to be the voltage regulator broke down its just a bolt on part and there is nothing you can do to it to fix it as its a "potted unit" if it is charging up the battery ok then check the battery it could be at the end of its life and cannot hold a charge or is not taking a charge the battery volts should read about 12.5 volts when not running and between13.5 - 14.5 volts when running but it may still not be putting out any amps
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First get hold of a volt meeter to see if the bike is charging the battery if its not charging then its likley to be the voltage regulator broke down its just a bolt on part and there is nothing you can do to it to fix it as its a "potted unit" if it is charging up the battery ok then check the battery it could be at the end of its life and cannot hold a charge or is not taking a charge the battery volts should read about 12.5 volts when not running and between13.5 - 14.5 volts when running but it may still not be putting out any amps