Quote Originally Posted by Owlie View Post
Yet there's still slack in the cable!
A while back at the bike co-op, there was a patron who was installing brand new low-end Shimano brifters. One of them just wasn't shifting right. It turned out that the head of the cable had popped out of it's little pocket in the brifter. This likely happened while the cable was loosened from the derailleur - the slack traveled up the cable, the head disengaged, and the brifter design kept the cable from self reseating. The solution was to take a little cover off of the brifter, reach in and reseat the cable, and then keep some tension on the cable until it was clamped to the derailleur.