Problems with front derailleur.

[neil180]

Hi
I have just done a complete overhaul on my wife's mountain bike, here is a list of what I have replaced;
Shimano MF-TZ 31, 7 speed 14-34 mega range cog set.
Shimano FC-M 171, 48\38\28T Chain set.
Shimano RD-TX35 6\7 speed rear derailleur.
Shimano FD-TX51 front derailleur.
Shimano CN-HG40 Chain.

I have adjusted and indexed the rear mech. The problem I have is with the front mech, I can change from smallest to largest cogs OK but when I change from the largest it changes to the middle cog fine but will not go to the smallest cog no matter what I do even if I disconnect the gear cable.

Has anyone got any ideas please.
Thanks
Neil

[cny-man]

Refer to the Parktool procedure, complete from the beginning, paying special attention to derailleur height and parallel to chainrings. http://www.parktool.com/blog/repair-help/front-derailleur-adjustments