Maybe someone will be able to shed some light on this issue. Shimano Ultegra 9 speed triple, front der is braze on. The problem is that when down shifting from the big to middle ring it often shifts all the way to the small ring. The logical thinking is the shifter cable is too tight. But if I make it any looser than it is then when the shift is made up to the big ring the der. housing rubbs the chain. 250 miles total on the group.
I have always set these things up according to the Parks book. Any other ideas than just keep messing with it until the sweet spot is found? Thanks in advance.