I upgraded from a CB300F to a CB500F and the buffeting is far more severe on the 500F under the same conditions (wind speed, temperature, motorcycle speed, gear). I believe it is partly because the 300F's radiator mounting point directs air downwards whereas the 500F's radiator mounting point has two vertical half-cones above it; I believe that this causes some air to go up and some to go down in a less than smooth manner as the air would collide with the half-cones and then create turbulence as air is forced one way or the other.