While doing some routine cleanup I noticed a gap I think is unusually large in the linkage of my early ‘70s (no circllip) fd. The gap is a little over 2mm wide. I disassembled it and the pin bearing at the center of the pivot spins freely and does not shift out. The cable pull vector may be pulling a little rearward but it running thru a fixed Campy bb cable guide so I can’t adjust that.

Is this normal wear? Should I be thinking replacement?

How about replacing the missing circlip on the post. You are missing s 20 cent part that makes the thing work correctly. Smiles, MH

There is no circlip on the early derailleurs. Not unusual. It can be fixed. You can tap the post for a small screw and put a small washer on it. I will share a pic when I find it.

Thanks Lynn, I’d appreciate that.

Yes, this is an earlier model with no provision for a circlip. The main spring tail secures the other link and I suppose the original designer felt this was enough to hold both links on. I’ve gotten well more than my due use out of this one but I like to give parts another chance.

The closed end sleeve that the lever arm slides over actually spins on an inner pin. Without breaking I couldn’t see if it was possible to secure with a screw. Looks like it can!

Photo as promised. I knew I had one that had been repaired. Bob Freeman did this one.

Thanks muchly, Lynn. Do the threads extend thru the mount body? I suppose I can tap drill thru and find out what’s in there.

I cannot answer that. I did not do the work and have not disassembled. I would think you would not want to drill very deep into the post, but that is speculation. Nasty looking. Crap on it from having our floors done. Need to clean it up.

It'll affect wear, and that will (further) affect performance.

Fix it or suffer.

This is what concerns me. The cage already wobbles through it’s travel. I was trying to solicit experience of how far I can let this go before performance really suffers or failure occurs. I’m supposing this wear is why the circlip was added to the design.

If I was really “OCD” about appearance then I don’t think I would be considering CV-6’s helpful suggestion to add a retaining screw.

Hi Alex,

I had the same problem years ago and it was caused by the pivot pin coming loose from its base. Campy later beefed up the base to resolve this problem. You have the earlier design. I bet that if you pull the derailleur apart you will find that the pin is loose, requiring either a new part or Bob Freeman's fix.

I'd think "appearance" would be impacted by the type of screw selected. Instead of a straight-slot head, perhaps an Allen-key buttonhead machine screw might look a little more Campyesque?

Actually, the first version of this derailleur had screws - flathead at that. Then they went away for a while, before coming back as c-clips. See this picture from VB:
https://velobase.com/CompImages/FDer...3B4C932DD.jpeg

I have had it apart as far as I can take it without breaking anything. What’s baffling me is that the post that the link arm pivots on is itself free to rotate but will not pull off. So this outer closed end shell spins as a captured part on a pin which is fixed to the mount body. I don’t know how the inner pin fixes to the body, whether it is integrally cast as a feature, or pressed in, or threaded in. My reservation about just drilling in is that I don’t know what the diameter of the inner pin will accept if I want to tap into it. I’ll take some photos as I tear into it and post them here.

The image of the mechanism shown might be too far gone to fix, the connection between the steel pivot and the aluminum body might be compromised.

the early design of this mechanism did rely on screws to hold the arms in position.
cost savings eliminated them no doubt.
the later circlip helped much.

my new in 1972 bike had the same affliction as yours, through the shop I later worked for, I got the body replaced under warranty. I was bummed that it happened, Campagnolo was on such a high pedestal.

Thanks for your experience perspective. I can see it degrading faster the wider the gap opens. Just don’t know when it would fail. If the cable pulled with less of an end load I don’t think it would have been an issue. I’ll rebuild it with some of the suggestions given and report back.

I was very bummed back then about it. I suggest take it apart and review the upper pin integrity.
The body on these was dimensionally the same, you could purchase a later circlip body (whole unit will be cheapest) with a CPSC lip cage and transfer the earlier cage and be in business.
Performance will improve.

OK, to close the loop I redid the offending pivot by removing the upper pivot pin (rhs in the photo), drilling through for a 4mm BHCS, made a brass bushing to thread onto the screw, and secured the arm with a nyloc nut. Both studs spun freely on the body, Both are steel and are 6mm diameter. The pin was anchored in the aluminum body by some sort of steel insert. I would have ended up tearing the whole thing apart if I wanted to find out the details. As it turned out I had to put a step extension on the brass bushing to fit into a cylindrical recess created by pulling out the old pin. The bushing is threaded so it snugs the screw head to the body. Anyway, I'm confident of the strength of the new pivot pin and all slop is now removed. The derailleur shifts more crisply too.





And a view of the finished new assembly. The hex head of the cap screw is visible as is the nyloc nut on the other side. Yeah, its not original in appearance but it has served me for 40+ years, so worth a salvage.

I would go very-old old-school: a slotted Fillister-head screw.

We’ll done Alex! That repair looks perfect. When mine broke back in the day, a magnolia still had their Craftsman-like warranty and replaced the part for free. I guess that warranty no longer applies to 50-year old products.