Hi...I just upgraded to Shimano 105 shifter levers model 5700 triple and I can't get the shifter to advance the chain to the middle ring in one motion. I need to bring it back and give another push. Is there a fine adjustment similar to the rear derailleurs to get it to advance just slightly? Thanks
With the front shifter in its lowest position there should be no slack in the cable.
Shimano road triple front shifters have 4 main positions plus a trim position for the smallest chainring. This allows for 2 positions for each of the 3 chainrings. Shifting from the smallest chainring to the middle chainring normally requires going to the 3rd position. Don't try to ease the derailleur into that position, just give the brake lever a good shove. When riding on the middle chainring use the 2nd or 3rd position for trimming. You should be able to make that shift with one sweep of the lever.
Glancing at the 5703 setup instructions, I see that they are the same as what I had to do for my 6603 levers. After adjusting the high/low limit stops, you're supposed to trim the derailleur so the chain just clears the inner cage plate when on the middle ring and largest rear cog. When doing this, the shifter is supposed to be in the middle ring position that is closest to the granny ring. I think this would be the 2nd position using Al1943's description. You get there by either:
a) starting in the granny ring and making a full sweep of the brake lever up to the middle ring (position 3), followed by a trim click on the inner paddle, or
b) Starting on the big ring followed by a full sweep of the inner paddle (Shimano recommends this method)
Needless to say, a barrel adjuster is highly recommended to dial this in just right.