I rrecently finished putting together a bike with parts from my 99 Cannondale, and other pieces salvaged from upgrades to my son's bike, onto a Sette aluminum frame. The bike is a back up bike for myself or my sons, who might need it as a spare. The 9 speed shifters and derailleurs are 105's. The chain is new and the 9 speed 12 x 25 cassette is fairly new. The bike shifts very well except it skips the next to last cog and goes right to the 25 cog. It while shifting up or down. If I adjust it so that it will grab the next to last cog it will not jump into the 25 cog unless I hold the shifter in. Is the front brifter shot? I can't think of any other adjustment to make that would effect the one cog and not the others.