Re original post. Motorized bikes don't make any sense. Either you want a slow ride with other cyclist or you want a vehicle that will keep up with traffic. It's too dangerous being the odd vehicle that drivers don't have experience with and will be more likely to either right hook or left hook you. FYI: a 500cc motorcycle is too small for safe riding with traffic. 750cc is minimum, but I wouldn't be comfortable on anything less than 1000cc.