Be sure your FD is just above the big chainring. If it is too high it will not work correctly on down shifts. Set height 1-2 mm (a US penny works) at the closest point above the big chainring. The "L" srew setting for the FD is critical. If it is in too far the cable will be slack, but the travel of the FD will still not be adequate for the chain to move to the small chainring. Also make sure the "H" screw is set for the RD so that the chain just barely clears the big gear on the cassette. It is best to have the chain on the small chainring - don't cross chain. A proper FD is radiused to match the diameter of the big chainring. Did you change the shifter from 3 to 2? The indexing is different, thereby the travel of the shifter controls the FD travel.