Originally Posted by
dr_lha
The CX70 has a different shaped cage that is better optimized for a smaller large ring (46T), but otherwise is identical to the FD-4600 in function (assuming you have the bottom pull version). However that shouldn't affect the function of the FD when you're in the small ring at all, so I would be willing to bet that a better adjustment of the derailleur is needed. I assume you had to move it up the frame when you put on a big ring? Make sure the FD cage is correctly aligned.
You will be right with that. What I have set up now is a compromise to let me achieve as little noise but this does mean some noise on both rings. However, if I was to properly set it up, I may be able to eliminate the noise on one ring but more on the other.
I did move the derailleur up the frame a bit and tried to make sure that the cage was parallel with the big ring. Measured the height from the teeth, etc.
If I am right, the images I have seen of the the cages seems to suggest that the 4600 is slightly less curved and maybe a little longer than the CX70?