You have to be careful mixing and matching Campag rings - they are not all the same thickness and you can hit issues there because the rings are supported from both inner and outer sides - so if you get a mismatch of ring thickness, you can end up with a kink in the rings where they pass behind the crank. It's not a massive issue a lot of the time (some rings are *made* less straight than the Campag rings end up) but occasionally you'll get chain drop because of it and you can't set the FD up spot on. Less of an issue with 53/39 than it is with 50/34 or 52/36.
If you start chucking 10s ring onto and 11s crankset, the whole problem might get worse.
The 10s rings are too far apart for reliable use on an 11s system - shortish chainstays + big %age difference in chainring diameter + wide cassette may end up with a slow upshift (and sometimes people leaning too hard on the upshift lever and thereby breaking it, in an attempt to use brute force and ignorance to do what the engineering is struggling to do), and / or the chain sitting on top of the inner ring teeth on downshift, not meshing - well, they're your soft dangly bits that will potentially suffer, but me, I'll take 100% functionality any day :-D
Before someone pulls me up on it ... although the centre-line of the teeth on the new hydraulic optimised (HO-type) 11s ring pairs are further part than 11s of old and in fact are very close to the 10s spacing, the HO outer rings are very specifically shaped at the back both to aid upshifting & in order to drop the chain into the small ring on downshift without that problem occurring ... in addition to which the teeth are actually milled offset slightly so that the material of the rings is actually almost the same distance apart as the old 11s ... compare a 10s and an HO ring and it's immediately obvious.
Silver 5 arm compact rings to suit Athena are still available from Campagnolo - FC-AT650S for the outer and FC-AT234 for the inner. Both are currently in stock at Campagnolo, I just checked - and (am I allowed to say this here?) we can order them for you for delivery week 2 of this month. Just drop me an email to velotechcycling"at"aim"dot"com ....
