My tach shows about 1000 rpm per 10 mph +/- with the 16 tooth front sprocket..... very handy. It'll cruise all day at 60 mph. and you can get all they way thru an intersection without having to upshift.
My powerband really doesn't taper off until about 7000 rpm. Cruising at 70 is out (with my 280 lb ass aboard). I
do use (not abuse) all the power she has.
The GeeZer is what it is, but it's even better when you wind it up a bit.
