Welcome to the site !!
That tag just is a easy way to know the year of the bike , the 10th digit in the Vin # is the year of the bike , so if the 10th digit is a 7 then its a 07 , simple as that , you mention not having a Title , if you bought it that way , the reasoning could be that it was not paid for and they were trying to hide its identity by thinking that if they remove the sticker , no one would know its a"wanted" bike ........*this is speculation on my part as i know nothing of the sale or situation surrounding it* , in my state you can't buy a vehicle or register it without a title or MSO Certificate (Manufacturer's Statement of Origin) , it can only be sold for "parts" and never be used as a complete bike
So before you get in over your head , i would suggest you write down the Vin # located on the Steering Stem of the frame on the right side , and call your local Motor Vehicle Department and give them the Vin # and have them check to see if it does have a clear title and you will be much better off in the long run , especially if you decide to sell it in the future , it just makes you the good guy in this and saves you a lot of heartache in the long run.....
Not saying you did anything wrong , but lots of people get told "stories" on why there is no title and accept the seller to be honest and end up in a legal battle or getting a visit from the local authorities and end up losing the bike and anything you have installed on it , as they will not let you remove anything from it if they are taking it , which would suck for you , if there is a legitimate reason for no title i would still get it just for your own well being , if the bike is ever stolen from you , you would have no recourse without a title
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