Sym GTS 400 and Burgman 400 are both 33 bhp, and just about hit 90mph, and accelerate at full speed to about 70mph before they start to slow down, The xmax 250 is nice to, wife has one, will do over 80 and silky smooth.

Howdy
A used Sym Joymax 300, Maxsym 400 or Kymco Downtown 300 may also be worth a look.