Could anyone help me understand what this part is called and how to avoid breaking it?
I had my Grx di2 RD fail and lose all tension today on a ride. At home I see that this shiny metal piece seems to be out of place. I was able to fix it by forcing the cage all the way towards the frame and it slid back into place. However I don't know what caused this, and I'm worried it will happen again.
by rowtohell
2 Comments
The parallelogram.
Corrosion.
Not fixable.
Wash and dry your bike. Just because it can get dirty doesn’t mean it’s supposed to stay dirty. The more expensive bike parts are the more maintenance they require.
It did not break, and you did the right thing.
That part is the link between the Di2 motor unit internals and the mechanical parallellogram of your derailleur.
It did not break, it’s just pushed out of place. That’s actually a design feature called Crash Mode. It allows the derailleur to move inwards when you crash to avoid big damage to the internal cogs.
You can either push it back manually, press the function button for over 5 seconds or simply click through all the gears on the shifters to reset.