My newest (2005 model) bike came stock with the typical useless massive racing crankset. To gear this baby up properly for climbing hills with a load in the trunk, I installed a TruVativ Hussefelt 44/32/22 crankset. (and the smaller BB to fix the new chainline) The front shifter is a 105 brifter, and original front derailleur was a Tiagra. The Tiagra's shifting worked, but it was rougher than I was happy with.
To see if I could improve the shifting, I installed a new X-Gen front derailleur that I had sitting around. The Tiagra derailleur had enough range to shift from little ring to big ring, but it didn't shift smoothly with the new crankset. OTOH, the X-Gen FD doesn't seem to have enough range, but shifts more smoothly. For now I am compensating for this buy turning the shifter's barrel adjuster to higher cable tension for shifting to the large chainring, and lower cable tension for shifting to the small chainring. This works, but is obviously a great annoyance. (Both limit screws are backed all the way out to allow maximum range, BTW.)
My question for the wise ones is...is there any reason the 105 brifter shouldn't be expected to work well with the X-Gen front derailleur? I've been adjusting all day, but I can't come close to getting from little ring to big ring without adjusting the cable tension barrel adjuster to keep the chain from rubbing the cage at either end. The height and angle of the derailleur look perfect to me, and this is not the first oddball FD/crankset/shifter combo I have set up, but it is the first time I've set up a FD with brifters, and the first time I've had this problem.
In fact the damn thing is even taunting me! If I optimize the FD to work with the 22 ring, and then shift all the way up to the 44 ring where the chain is rubbing the outside of the derailleur cage, then apply pressure to the brifter as if I was shifting up one more index position, the FD cage goes to the perfect place, but that is beyond the last index position. So close...yet so far!