the intake on your stock ciao case is only 13mm, so a 14mm carb won't really make a difference.
the gears in the rear end will keep you slow as well.
my ciao build is the 80cc pinasco kit, malossi reed valve case with the malossi crank, custom 21mm intake for a 21mm phbg, naz built cdi, simonini calibrata pipe, malossi variator, and the malossi gears in the rear end.
i'm not sure of what the performance will be like, but i hope it's pretty rad