With my '79 cb650 stock motor, cb750 carbs, pods, 17 tooth front gear, 39 tooth rear gear, I hit the 130mark on my speedo once.
Mind you thats with me lying on the tank pretty much.
scared the h*ll outta me!!!
Was at redline pretty much.
With my '81cb650c with stock gearing and motor, i dunno.
the speedo tops at 80.
I'm guessing just under a ton, but i had 2 grand to go on the tach.
l8r