RekabDot wrote:
I'm a big fan of "the simplest solution is the best."
Isn't the front derailleur simply too high? It is hard for me to tell for sure from the pictures.
I use qxl's and during setup the derailleur is just barely above the big ring, as close as I can get it without scraping the teeth while riding. Obviously, given the oval shape they move up and down within the derailleur therefore if it is a little high the chain will rub on the bottom. If the derailleur is a little low it will jam up and do odd things when you shift and it hits the big ring teeth. It needs to be goldilocks.
Also, I used the thin shim with the speed concept but none with the road bike. I don't think I need it on the SC but that was the first setup I did so I've just never bothered to remove it.
Other than the requirement to ensure proper setup I haven't had any issue with 6800 and qxl or qrings.
-Rekabdot
Disclaimer:I'm a self taught wrench so your mileage may vary and everything I say is likely incorrect.
I probably should have said in my post (I was in a rush to post before going to bed) but I also own a TM02 and had to use the shim. I had the derailleur as low as it could go and still work to get in the big ring and it was nowhere near close to avoiding the chain rub in the small ring. I guess this is where things like seat tube angle etc. have an effect.
My own experience with QXL rings was short lived, I pent a long time tinkering trying to get it to work but I still found the shifting to be too unreliable. The micro seconds I might have saved in watts were more than offset by the time I spent fixing dropped chains.
