After searching as much as I could on this beta vehicle it has come to my attention that it should be renamed Beta Streetfighter. In game if one look closely at the Streetfighter's license plate it has the number VC0601. On the screenshot depicting the bike being driven by an NPC it has the same license plate. This seems more plausible since the Streetfighter is an exclusive to Grand Theft Auto Vice City Stories. Please let us discuss this for others to share their knowledge on this article!