problem adjusting front mech

[al78]

One of my neighbours had a problem with her front mech, it wouldn't shift, so I offered to take a look at it. I managed to give it a thorough clean and re-lubed it and it now will shift. However after putting it back on the bike I am having real problems getting it set up right. I can set it up so that it will shift up but not down, if I set it up so that it shifts down as well then the chain will rub on the front part of the cage. I can't get it right even using the barrel adjuster. One thing I did notice is that the cage does not seem to be parallel, it seems to bulge out slightly, which begs the question of how to get it parallel to the chainring if it is not straight. I have attached a photo of the mech on the bike, is the cage supposed to be bent like that or is it likely that it has taken a knock?

 

[Garz]

Seems a bit bent that. I haven't had to adjust a triple mech yet though so can imagine them being a ball ache. The barrel adjuster made a big deal to my problem the last time, however I think tightening the wire to the mech made some difference too as it must have stretched over time. To do that though requires three hands or a lot of patience.

 

[PatrickPending]

does look a bit bent to me, though for a mech that shifts up easily and not down i'd lube it (like you have done) but also replace the inner/outer cable - if they're old you can have problems here due to friction.
If it were me i'd replace inner and outer and take it from there....

 

[Red Light]

Doesn't look too bad but for a starter and some are curved like that. It might work better if its not parallel to the chainrings mine are toed in slightly at the rear. The Shimano instructions for setting it up work very well but basically you set the cage for the big and small ring using the limit screws and then set it centred on the middle ring using cable length and the barrel adjuster.