As far as I know, GRX shifters are only available for hydraulic disc brakes. Does your bike have disc brakes? However 105 11 speed shifters will work with a GRX rear derailleur. A GRX front derailleur will not work with your Dura ace crank, due to chainline issues, but a 105 front derailleur will work with it. So, what you need is a pair of 105 11 speed shifters, a 105 front derailleur and a GRX rear derailleur
Last edited by alcjphil; 11-27-22 at 02:08 PM.