Front derailleur problem

[Sardine]

Thanks lph. Just turned the bike over to check. The cable routing is fine but I've just noticed that maybe the cable is not in as good condition that I thought as there is some rust down there.

I can feel the cable tension changing when shifting up but there doesn't appear to be movement as I shift down and the derailleur is sticking on the downward shift too. In fact I'm noticing that the shifter is also sticking. Instead of springing back up automatically, I'm having to nudge the thumbshifter then everything moves. I have lubed the derailleur but possibly not enough on the pivot points. Will try what you suggested.

Thanks again.

[Velocivixen]

Is there grit inside the cable housing that could be causing a problem. I know that it might be unlikely, but just a thought. Hope you can get it resolved.

[DebW]

When a front derailleur won't shift to a smaller ring, it's often that the cable/housing needs to be replaced. LPH gave good advice about separating the effect of the housing from the effect of the derailleur itself. There are also small adjustment in the derailleur that could affects its shifting, eg, the stop screws and the cage angle and height. Shifters can also get sticky and stop working properly, so squirt in some lube, or soak in solvent and relube.

[Sardine]

Thanks Velocivixen and DebW. I've relubed all the pivot points on the derailleur as lph suggested and the shifting has already improved, but it's still sticking a bit. I haven't checked the cable housing yet but will do that in the next day or two when I have time to remove the bar tape etc. I think you're all right about the cable/housing. Probably time to change it or at least clean it out. DebW, it didn't occur to me to lube the shifter. Thanks for that.