Originally Posted by
cyclingman1
...Yes, the 11 speed FD is considerably more narrow than is the 10 speed. There is a hard plastic cage edge that suggests that a certain amount of chain rub is expected. Virtually every adjustment of my FD was off a little. I now have a couple of more gears with no rub at all. This FD makes using the small CR imperative if one does not want rub when going to large sprockets...
Numbers do matter. Are we talking FD-6800 or FD-R8000? And the crankset? And the shifters? It's possible to predict the behavior [of your new combination] by simply knowing what parts are involved, their compatibility and their spacing.