Page 1 of 1

Campag Front shifter sticking

Posted: 6 Mar 2012, 11:44pm
by Andygreenham
Having a bit of trouble with a Veloce front shifter from around 2006. It randomly jams up completley and won't allow me to shift down. I have to first tweak it up a notch before I can shift back. Has anyone else experienced this problem and is there a way to fix it ?
Its particularly annoying when you have just flown down a hill and as you start to climb again all momentum is lost as you fumble with the gears.
Any ideas folks ?

Re: Campag Front shifter sticking

Posted: 7 Mar 2012, 1:15am
by g00se
Hi,

Is it an Escape mechanism (one click per chainring going to the smaller ring/s - but two going up)? I had something similar on my wife's bike and sometimes needed to push it back up one trim ratchet. In the end, it was mis-setting up the tension against the bottom stop.


I'd suggest releasing the cable from the mech - check the cable friction/movement - then set up again as per the campag tech manual on their website.

If that doesn't help, then the ergo may need a strip down and clean.

Re: Campag Front shifter sticking

Posted: 7 Mar 2012, 3:04am
by Brucey
when you look at the mechanism inside, it is difficult to see how this could happen. After all, inside, the arrangement with the 'G' springs isn't that much different now to how it was when they first came out, even if they feel and work a little differently.

However, if you have ever run through the clicks with the cables disconnected you will know that the thumb shift can feel surprisingly stiff when there is no mech pulling on the cable; this would make me want to check that the mech wasn't binding and that the cable run was OK before doing anything else; if the cable isn't pulling back well enough the shift will be hard and may feel like something has jammed. Similarly if the ergo needs some lube internally it may also make it more reluctant to shift.

BTW presumably because ergos don't have so many small parts which articulate under low load (really only the thumb lever I suppose) they recommend grease as the ideal lubricant on the detent wheel; (whereas the superfically similar Shimano STis generally do have more small articulated parts inside, and seem to work best with a thinner lube) . However it doesn't stop you from using a (temporarily) thinner e.g. spray lube (with a solvent carrier) in an ergo as a diagnostic tool, provided you are happy to lube the ergo properly afterwards if you have used the 'wrong stuff'. Some spray greases seem OK to use in ergos, others not; but if a thin spray lube has washed all the grease out or the mechanism is dirty, the best recourse may be to dismantle the ergo to lube it properly.

If none of this works out, it may be that one of the 'G' springs is jamming for some reason, or another spring is broken; these parts don't last for ever and some recommend that they are routinely replaced at intervals as part of normal servicing.

cheers

Re: Campag Front shifter sticking

Posted: 7 Mar 2012, 6:23am
by johnb
Andy, check that the rubber from the grip is not jamming the mechanism. Sometimes this happens after you put new bartape on and don't put the ergo hood back on properly.

Re: Campag Front shifter sticking

Posted: 7 Mar 2012, 1:10pm
by PW
Johnb is the suggestion I'd try first, closely followed by the bar tape. After a couple of run ins with this I always check with a sharp pocket knife before riding it.

Re: Campag Front shifter sticking

Posted: 9 Mar 2012, 6:44pm
by Andygreenham
Thanks very much guys, with your suggestions in mind I shall venture to the bike shed again this evening.
Andy