going to chime in late but my FD is doing exactly the same thing. It’s 2018 or whenever they first came out. I had to wait for them to be delivered it was that new.
anyway you have helped confirm my worst fears… Time for a new one and in Australia stock is VERY limited…
Hi there - were you every able to fix this issue or did you have to get a new FD? I am having the exact same problem and wondering if there’s a fix. Luckily in my case it’s a GRX 815 derailleur so still under the two year warranty - so I’ll send it back but just wondering if you have any luck sorting yours out. Hope so!
I have the same problem with my GRX 815 DI2 bought in February 2020. In Europe there is a 2 years warranty period (3 years for Dura Ace and XTR) so I will have to live with it or buy a new one. Does anyone know the cause of this or has a fix for it? I believe the FD is also more nosier since this problem appeared.
Update March 2023: After months of riding around with this problem, the front derailleur has completely failed. Finding it absurd that such a part could fail so quickly, I sent it back to Shimano. Despite the fact that the warranty period was over, I got a new one (goodwill arrangement). I still don’t know what caused the problem.
It looks like this problem has everyone stumped and that the only fix has been to get a new FD
Did you end up getting a new one ?
I didn’t and was still able to use my bike to good effect on several tough climbs in the Alps this summer (Alpe d’Huez, Sabot, etc…) I just need to remember to be in the small ring before it starts to climb in earnest for a long stretch !
What’s weird is that when it’s on my HT if I don’t touch the bike for several days, action on the left lever will trigger no response until I push it in manually once and then it’s fine. Outdoors I’ve never had to do that even after several weeks…
ok so I finally got a new FD, did a straight swap and…it works as expected, no issues shifting down under load. Hope that helps those facing the same problem down the road (i.e. no down-shifting under load and no problem shifting up under load).
@ coolpluggy - saw your update, guess it was a blessing to have it fail completely and nice gesture from Shimano