Darn , darn , darn , you've infected me with a desire to have a 4 wheel Vespa . Now I don't have one to start with so I'll to start from scratch . Besides as nice as the molded metal is I just think it will look so much nicer made from fine wood work . I'm also inspired by this cool project [link]
btw, I don't know if this qualifies as great minds think alike but . . . [link] I almost made a "Quad-rophenia" bike. I would have too if Second Life's Linden Lab Lawyers hadn't pulled it's copyright bullshitery.
But this needs to be done. Your scooter creations are second to none!