I finally had a chance to ride my '82 Zilioli, all Campy SR, all original, EXCEPT for the chain. I put a 9sp chain on it a few years ago so I could ride it with my 9sp Velomax Tempest wheels instead of the original tubulars. The tubulars were in bad shape, or so I figured.

I put all the original components back on it, including the 6 speed tubulars, built with Campy hubs and Nisi Laser rims. The problem I had is that in the middle cogs the chain would slip. It wasn't engaging the cogs at all. This didn't happen in the top 2 or bottom 2, just the middle. Is this just due to the 9sp chain? Or are the cogs worn, or most likely both. I ride my other vintage bike with a 10sp cassette and chain (same Velomax wheels), and an old Zeus crank from the 6 speed era. No problems with that bike.

As for those tubulars, one is a Clement Criterium, the other is a slick of unknown origin, the label has faded beyond readability. Both are old but held up for a 15 mile ride. I didn't trust them on the downhills and took it easy although they did OK on the flats when I turned it up a bit. Maybe I'll buy some new ones, or more likely I won't ride it enough to bother.

Are you running a Regina freewheel? I have a 13-15-17-19-21-23 Regina America on Capo #1, and my SRAM "8-speed" PC-58 chain occasionally skates over the tops of the teeth of the 17, 19, and 21T cogs. I have attributed this to a combination of tooth wear, Regina's squarish tooth cross-section, and my 2-tooth cog size progression. I have to be very careful to engage the chain completely onto the cogs before applying much torque, which is generally not a problem if I use proper old school non-loaded shift technique.

I couldn't really see what it is without taking the wheel off. But it started to slip even after I had it in gear. Looking at it now though I can see how narrow the chain is with the teeth barely fitting into the inner plates. Maybe I should get a wider chain. Either that, or get a 10sp chain and use it with my 10sp wheels.

At this point I'll have to say I won't be riding it much. It is still February.

C'mon Zacster! Throw on some tights and balaclava and hit that Prospect loop! I was just posting about chain slip and Regina a few weeks ago. Rebuilt a Ciocc with all Super Rec stuff and I was slipping in the middle of the cluster also. I switched out the Regina freewheel and all is well. I'd say your description sounds exactly the same as what I was experiencing, but you've also got the wrong chain on there. Throw a 12 dollar fewer-speed Z-chain on there (Recycle has 'em in Dumbo). If it's still skipping it's your freewheel. Only thing is - I think if you want to switch to 10 speed, you'll have to cold set the rear dropouts to fit the 130 spacing.

I've been out there, just not 3 or 4 times a week, only weekends. I'll try the cheap-o chain on it, since the 9speed won't do me any good with any of the other wheels I have, they're either the old 6 speed or new 10sp.

I used a 130 spaced wheel on it without any problem a few time before when it still had a 9sp cassette on it, hence the 9sp chain. Now that wheel has 10sp. I was trying to get a Shimano wheel to work with my 10sp Campy setup on my Kuota. The Velomax/Shimano wheels were better than the Campy Vento that I use on it. 9sp didn't work, nor did 10sp, even though people say it will. There's always a gear that doesn't go in, and there is always noise until you adjust it with the shifter.