The large lever can’t be moved more than a short distance to where it would normally start moving the cage but won’t move any farther. It doesn’t move the cage at all. Something in the shifter is preventing full movement. Local shop replaced the cable and sprayed some cleaner and lubricant in the shifter mechanism and it will now sometimes shift, but generally doesn’t.
I can move the cage by hand over the large chain ring then the shift lever can be moved as normal and will hold the cage in the large chain ring position. Shifting down to the small ring from there works fine. The lever usually just hits a hard stop and the cage doesn’t move at all. But again, the cage can easily be moved by hand so the problem must be in the shifter.
I’ve ordered a new shifter from the shop but it would be nice if we could fix it instead of full replacement. Shimano Ultegra R8020 on a 2016 BMC Road Machine Two 02.