Sticky front derailleur

[niklasvm]

Hey

I've been having problems with the front derailleur on my road bike. It doesn't want to shift down at certain times, mainly during or just after riding in wet weather. I am able to push it manually with my hand to the right position but this is not optimal for riding.

 

As far as I know when you shift down the cable relaxes so its the mechanism which moves the FD back to its default position that is struggling

 

Seeing that it works fine when its dry, could it be water or dirt that gets in? What's the best way to clean or lubricate the mechanism?

[Mecnic]

Usualyy its a combination of your supplements and dirt that jam up the mechanisms and make it stick, Clean it with some warm soapy water let it dry, you can even use an air compressor to blow away any excess moisture.

 

Also check the cable is running smoothly through the cable guide and housings this may also get jammed up and make the cable stick.

 

after all this is done (I'll probally get hounded here) but I use a little q20 in the pivots of the der to lube things up, please remeber q20 does atrract dust so use very little of the stuff and wipe off any excess.

 

Hopefully this will solve this problem but also remeber there can be a whole host of things wrong this is just one of the more common ones.

[David Marshall]

I'll bet a new cable and new cable housing will solve it but check out the plastic cable guide under the BB shell as well.

[niklasvm]

the cable and cable housing were replaced recently. I don't think they are the problem. The cable moves fine, its the actual derailleur that does not move into place. You need to give it an extra push to get it to the right position. I think it might be that the rivets are worn.

[Mecnic]

Post af few picture of the der that we can get a better Idea of how it look, Ypou'd be suprised how much sugar and road gunk can jam up a der try what I said and give it a good clean and lube with warm soapy water the warm water helps dissolve the gunk out of the pivot points and bushes.

[niklasvm]

I spent about an hour yesterday with a toothbrush, some paraffin solution, soapy water and lube washing it. The derailleur looks brand new again but still gets stuck. I'll try get a pic up.

[Vivster]

Also had the problem on my MTB. Some CLeanGreen, a toothbrush, new cable and housing and gone was the sticky FD

[kosmonooit]

Take it off to isolate the problem to the Dérailleur to be sure. If penetrating oil wont fix it after a good clean, then you are probably looking at replacing it, the pivots pins are prob. corroded inside.

 

How old is it? make / model?

 

I recently suffered from a double bout of SDS (Sticky Dérailleur Syndrome) with some new SRAM X9 RD's,but that I proved was a manufacturing fault: one was credited from CRC, the other I got locally still waiting for a credit/replacement. I now have X0 RD's which have cir clips on the pins that you can take it apart to clean/ service, but I havent managed to find a front one with the same system of dissembly ie they all seemed to be riveted.