Front derailleur cable adjustment

[jorgemartin]

Hello! I have installed a new front derailleur. I believe everything is okay as far as the positioning, the distance from the teeth of the big chainring and being parallel to the crankset. I run the gear cable through the shifter, down underneath the bottom bracket and there comes the cable up again and I clamp it to the derailleur. But when I change gears going from small to big chainring is like the derailleur doesn't want to go up and it reverts back to the smaller chainring. Is this because the cable is too tight to start with? Is there anything else I should be considering? I destroyed a cable yesterday and would like to get it right before I destroy another one. I'm using shifter levers that are attached to the tube. Any ideas? Thanks!

 

[akb]

Did you tighten the cable finger tight or did you use pliers?

 

[jorgemartin]

Finger tight.

 

[betty swollocks]

Are you using down tube friction levers like these?
If so, maybe increase the friction on the lever. This will prevent it snapping down to its default position ie into the small chain ring.

 

[jorgemartin]

These are the levers: http://www.flickr.com/photos/jorgemartin/8266970259/sizes/o/in/photostream/
Betty, what do you mean by increasing the friction?
Cheers!

 

[boydj]

You could check by moving the shifter mechanism by hand with the cable disconnected to see if your upper limit screw is far enough out let the mech get into position to get the chain onto the big ring and not interfere with the chain when it is on there. When installing a new front mech, I'd start with the limit screws giving maximum movement and then tighten them in once I know how far the mech needs to move to shift the chain efficiently.

 

[jorgemartin]

Sorted! Fine tuning the cable tension did it. Thank you all for your help!