Originally Posted by gfk_velo

This answer should be qualified insofar as it will work OK in most cases but the Athena RD has a weaker return spring than the Chorus RD as it is designed to work with the PowerShift lever - if the cable run is long, or complicated, the RD won't shift as well as any increase in the friction between cable inner and outer can cause a problem in set-up.

You will also see a more sluggish shift, especially under load, to the smaller sprockets than you should - as part of the RD return tension will be being used to help rotate the shifter innards, rather than trying to pull the chain off the sprocket.

Once outer cables are significantly dirty / worn inside the curves or in the case of the tunnels, start to gain wear or get claggy with energy drink residue and the like, you may again see slightly less good function, again because the RD only has so much spring tension to "share out" between rotating the lever innards, overcoming friction inside the gear outers and pulling the chain off one sprocket and onto the next.

So the message is generally yes, it will work but it *may* not be perfect and if it is when installed, you may need to look at a more frequent and careful maintenance regime to keep it that way.

HTH
Graeme
Campagnolo Main UK SC