Welcome to the site from New Jersey, nekidone!
I'm curious, does your R3 have its original battery or can you find out from the prior owner when he got a new one? Also, do you have a Battery Tender?
Hellfire's your man as far as the Odyssey upgrade goes, but I'm fairly sure that he'd advise you to get the Odyssey charger, too. It is specific to that battery - a Battery tender will not fully charge the Odyssey battery.
In any event, do enjoy the ride, Captain and let us know when we can organize a group ride to Tahiti!