I'm building up a new custom bike (or will be someday in the future when the frame arrives from England!) and my intention is to make it all Campy. As much as possible, anyhow. I already have a lot of parts - headset, seatpost, hubs, brake levers and shift levers - and while these themselves aren't from matching Gruppos they are quite lovely and I'd like to stick with the theme. Brakes will have to be Tektro as I need a standard-reach brake and you have to go WAY back to find a campy brake that's anything other than short-reach.
Anyway, all that really doesn't matter so I'll get to the point: I live in the mountains and this will be an all-rounder bike. I'd like a Campy triple but they come with 30t inner rings. I'd like something smaller but haven't been able to locate it - haven't been able to locate ANY size other than 30t. So the question is: are smaller chainrings available for the Campy triples?
You can get a T/A Specialties 74 BCD small chain ring in 24 thru 30t that will fit the campy triple. Contact Peter at Vecchios in Boulder. I have a touring bike setup and I use the campy Centaur group with a triple crankset. I replaced my 30t with a 26t and the large ring is a 50t. The cassette is a 13-29t combination. Works exceptionally well. Google Vecchios and give peter a call he can help you with anything campy.
I put a 24 on my Campy Mirage triple but the jump from mid to inner is a bit rough and sometimes it misses the ring and hits the BB shell. The front mech moves diagonally downwards; the new small chainring is much lower down but no further away. Eventually I switched to a Shimano LX chainset and lowered the front mech. It works well enough now to ride mountain trails.
Consider using a 13-29 cassette as a first step. There are plenty of compatible chainrings already mentioned, but I would start with a 28. I used a 53/39/28 for several years in the Colorado mountains with no problems. My drivetrain was 10 speed Campy with a 12-25 cassette, but I do have a 13-29 cassette and used it in the early season. The 28/29 gear was so low that I only shifted into it a time or two. You will need a long cage RD is the 13-29 cassette is selected.
I use 26 and 28 TA rings on my Campy triples. For the 26 I use a chain watcher to prevent the chain falling off to the inside but it is not needed on the 28. Wiggle has them in silver and black for about $24 but the 26 is not in stock now.
OK, cool. Anyone know where I can get one with the 30/40/50 rings? Everyone has the 30/42/53. I have no use for that big ol' ring and 42 is a pretty big step from a 26.
I know exactly what gearing I want. I have smooth dirt trails around my house that are EXTREMELY steep (the rocky stuff is up higher). I put my MTB in 24-32 on part of it! This bike'll be somewhere between a cyclocross bike and a touring and I can use a higher gear on that section (or walk for that matter) - but 30-28 ain't gonna do it! I need a nice small bailout ring.