Here is a new one for me. I have a Pinarello frame that I just installed a vintage set of Shimano 600 components on. When I tried out the shifting I find that the chain rubs on the bottom back stop of the front derailleur. I then went to my parts bin and took out a vintage Campy front and tried it and the same thing. It seems that the smaller chain ring is too small and causes the chain to bottom out on the derailleur. I cannot lower the derailleur any more as it then hits the larger ring when shifting. What's up with that? The frame is the type where all the tubes slope inward, could that be the issue. Also the cable routing is internal so there is not a lot of room to play with. A funny side note about the internal cable routing. I thought most manufactures would have guides internally to help route a new cable. Much to my surprise, I found that there were no cable guides and I had to remove the BB to re cable the derailleurs. I also noticed that there is no protection for the cables inside the BB shell. They actually rub against the raw tubing as they go from the down tube to the chain stay and seat tube. Lousy design if you ask me.
Ray Homiski
Elizabeth, NJ