Originally Posted by
dsbrantjr
I would suggest that you check for excess friction in your shifting system; inability to find a cable length adjustment which suits both up- and down-shifting is often indicative of a friction problem. A common culprit is the loop of cable going into the derailleur; it tends to collect water and road crud. The other cables can likewise collect sweat and other contaminants.
Never would have thought to check that! Makes sense though. Wonder if the housing needs replaced anyways? I've had the same housing on since I bought the bike back in 2012.