Are you positive you have a triple front shifter? Does it say triple on it? A 7703 will say triple on the name plate. Double shifter will have a sort of third click as there is often a trim click (at least on most shimano). I think the trim click is in the small and though I have worked on many shimano equipped bikes it has been a few years and I don't have and shimano brifters on my bikes so can't recall where the trim click is on 7700 or be sure that is has one.