Had another go at the R8000 FD and it's better but still not perfect. Rubs inside the cage at the extremities. Turns out you need to start with it piss, not straight and once it's bolted to the braze on, then you use that stopper screw to push the arse end straight. It still barely clears the crank arm when it's clearing the chain though. Next thing to try is that cable tension screw. It didn't even look like an allen key hole on this FD, it looked like a pin but watching a vid it turns out that little bastard should be right out when you pull the cable through and then you can get the cable tighter with the 2mm cable tensioner. Not sure how much difference that will make to the actual cage position, but maybe it means it will move slightly further out with a lever throw so I can back off the H limit and then it won't be so close to the crank arm, but then again that doesn't make sense to me because the cage should be parallel anyway so it doesn't matter if the cable moves it or the limit screw moves it, right? Only one way to find out..
Turns out you need to start with it piss, not straight and once it's bolted to the braze on, then you use that stopper screw to push the arse end straight.
I did. My Di2 was never this much of a dickhead and that got a fair bit of tweaking done to it with different ring sizes. Maybe I just got lucky with it. Did they shrink the cage width or something?
Had another go at the R8000 FD and it's better but still not perfect. Rubs inside the cage at the extremities. Turns out you need to start with it piss, not straight and once it's bolted to the braze on, then you use that stopper screw to push the arse end straight. It still barely clears the crank arm when it's clearing the chain though. Next thing to try is that cable tension screw. It didn't even look like an allen key hole on this FD, it looked like a pin but watching a vid it turns out that little bastard should be right out when you pull the cable through and then you can get the cable tighter with the 2mm cable tensioner. Not sure how much difference that will make to the actual cage position, but maybe it means it will move slightly further out with a lever throw so I can back off the H limit and then it won't be so close to the crank arm, but then again that doesn't make sense to me because the cage should be parallel anyway so it doesn't matter if the cable moves it or the limit screw moves it, right? Only one way to find out..