I just installed my Dura ace 7800 wireless SRM, replacing the existing dura ace 7800 crank. The chain is rubbing in the big chainring now. It didn't do this with the previous crank. Does anyone know why the chainrings aren't in the same position as before? Did I install my SRM incorrectly? I didn't change BB, I just took the old crank out and put the new one in.