How to solve a chain rub problem.
 

I'm experiencing chain rub. The drive train is Campy Record from 1984, two chain rings, six cogs. The outer edge of the chain (which I had to replace) rubs against the inside walls of the front dérailleur cage when in the first and sixth cog. It doesn't matter which chain ring I'm in. I can trim out the rub using the front dérailleur lever, but I can't believe that should be the norm. I've tried adjusting the inner and outer limit screws on the front dérailleur to no avail. Could the chain be too wide? Does a Campy drive train require a special (Campy?) chain? What's going on here?
Tsapp

Trimming the front derailleur is how you solve chain rub.

[MENTION=145941]tsappenfield[/MENTION] - is your FD adjusted correctly? Outer plate parallel to the outer ring, plate clears outer ring by 1 mm. If so then, it is normal, even for 5 sprocket blocks with original chains. Using an 8spd chain might decrease the rub issue.

How did you replace the outer edge of the chain?:)

Pretty much all the advice you need in the two posts above. Check what #2 advises, and then, accept that some trimming of the FD is inevitable - even on modern drivetrains.

Even with proper and meticulous tuning of the front derailleur operation you will still need to trim.

The beauty of the friction front is the availability of infinite trimming.

Trimming a friction shift transmission is pretty normal, in my opinion. I have set up lots of systems, and, no matter what, if it is friction, one must trim to achieve optimal positioning, be it the front or rear derailleur. After a while, trimming becomes automatic - well for me, anyway.

I just went through re-habbing this 1977 Ron Cooper road bike, which included re-spacing the rear to 126mm and rebuilding/re-dishing the rear hub/wheel for use with a standard-spaced 6s Uniglide freewheel.

I initially fiddled with the bike's original Ultra-6 freewheel and 8s Sachs chain, during which I spread the front derailer's cage to completely eliminate any need for front derailer trim across the entire freewheel.
I used a long-handled duck-bill plier, pulling the handles apart to apply a parallel spreading force inside, up near the top bridge of the front derailer cage, so the result looks normal and the cage plates still look parallel and undisturbed.
And when I installed the re-spaced wheel with the standard 6s Uniglide freewheel, I also switched to a Shimano 9s chain, so I can now still use the entire freewheel while on the big ring with no need to trim the left/front shift lever.

I am really enjoying the light, forgiving shift action of this setup, after also lubing the shifter and cable/housing. I've been riding it hard all week and have not tossed the chain even once after making these mods, so can recommend this.
And luckily for me, this bike's Stronglight crankset has no problems with the 9s chain, that being a surprise.
I have to say I prefer this bike's friction shifting to any kind of brifters or indexed DT shifters, it's that good.
Thanks to Joe E. for the bike, and for the 13-26t Uniglide freewheel!
BTW, I switched between brand-new SRAM and Shimano 9s chains, and the Shimano chain shifts more responsively.
The duckbill plier is a very special one of my tools, and not the easiest thing to find.

This Cooper is a keeper.

https://farm1.staticflickr.com/460/1...cfa82fce_c.jpg

https://farm4.staticflickr.com/3745/...8f04c386_c.jpg

I had some chain rub problems on the outer chainring when I was on the little cogs. An 8 speed chain solved that.

My understanding is that there is no difference between chains on a 6/7/8 speed bike. I don't know if that's true for Campy. However, 9/10/11 speed bikes still use chains with identical inner link chain width to the 6/7/8 speed chain, its only the outer link width that gets thinner, thus making the chains marginally weaker. However, you could try to run a 9 speed chain to see if the marginal difference allowed you to not ever have to trim. Or go single speed and avoid shifting altogether.

The beauty of Campagnolo Ergolevers is the ability to adjust the front derailleur front trim. I hate indexed front derailleurs like Shimano and SRAM. My X.9 mountain bike constantly gets derailleur chain rub in some gear combos. Indexing makes zero sense on the front derailleur. Being able to trim is a good thing.

To be honest I have never had a chain rub on both the 1st and lowest (6th, 7th, or 8th) cog without an adjustment problem. As others a said , generally you adjust the derailleur for the large (outside) chainring to run with the smallest cogs and the small (inside) chainring with the largest cogs and let the trim occur as you move across the cogset. Keep in mind that using all the cogs with the same chainring does result in chain crossover.

I have done a few things to adjust it that may require a small height change, or slight angle, or maybe adding a washer to spread the cage slightly. These are just small tweaks. You may want to see if there are any other Campy FD that will have a wider cage or mod it as described above if you have the intestinal fortitude.

John

It is possible to not have to trim. I have a bike with a 6 speed block on back and double up front and I never have to trim the front. It's more by luck than design but it is a real pleasure to use. I prefer it to a brifter it's so fast. Sheldon indicated it is possible but probably only with select setups.

I have found that a slightly loose chainring bolt or two will be enough to cause chain rub on this bike so might be worth checking those.

Edit: Checked the cross chain combos (gears 6 and 7) and no rub there either. Chain is a fairly modern design - not sure what width.

Yes, only a few rare configurations do not require trimming, and probably only if one eschews cross-chaining. I have never considered the need to trim to be a big deal -- I just do whatever is required, and across a 6-speed block I probably need only one, maybe two, trims.

Yes, with select setups and with at least a somewhat-modern chain, trim-free shifting is a wonderful reality, especially when hammering over hills in order to hang with a pack of riders.

Yet it was that I got spoiled by such a setup which forced me to adopt any needed measures to avoid ever having to trim the front shifter on any bike that I ride, even indexed front derailers, and yes, I do cross-chain!
I usually start by working with whatever chain is already on there, and then as 70sSanO described it is a matter of observation and little tweaks to arrive at full clearances for the chain without undue trauma or disfigurement to the front derailer!

Lastly, the narrower chain can go on to further optimize everything, and the narrower chain eliminates all traces of rub.

Chains have not gotten weaker with each narrower version. Almost every decent chain today is able to handle mountainbike drivetrain use, which is far, far more severe than any road bike will give it. Yet defective chains do occasionally pop up.

Inside width of various chains are not quite identical, but I've found that 9-speed chain seems to run on every road sprocket I have tried it on, even old Varsities. Certain cranksets space the chainrings too far apart for use with 9s chain without tooth modifications, but I get them all to work.

The biggest change is always when removing old 5/6-speed width chains, which are nearly 8mm wide, and replacing with 7.2mm chain (7-8sp) or 6.6mm chain (9sp). I have yet to use 10sp chain on any vintage bikes, haven't had a reason and they only cost more.

[MENTION=185430]dddd[/MENTION] - Thanks for the info in #8 ! I will start playing around with my favorite rides based on this info!

The Pinarello has DA 8spd 7400 drivetrain and is nearly rub free. I can barely hear it in both extremes. Perhaps a little tweak here and there will eliminate the rub.
This info will help me attack the tandem issue too along with the Colnago. In a grab bag of parts purchased within the last year, were two 10spd chains. My try them out too!

The Ron Cooper is definitely a keeper! Looks hot and a joy to ride. Bikes like yours are very C&V in my book, simple, elegant and purposeful.

I have sometimes widened the rear end of the FD by adding a longer spacer to the cage. This helps with wider clusters.

You pop all the pins and replace just the right-side side plates. It is a lot of work but can be done. It won't gain you anything unless you use thinner side plates. :D

It's easier just to replace the whole chain though.

I don't mind some minor adjustment. But I'd advise at least checking the FD position.

While you have the side plates off, follow Sheldons thorough cleaning approach of disassembling the whole chain!:)

Shimano has always been parallel, but I think on Campy of that vintage, the FD cage maybe is supposed to have the back side turned in by about a mm.

Find another old timer to be sure though. We didn't get much Campy in the shops I worked in back then and I didn't get to work on it very often.

IDK, that approach is counter intuitive to me. The back side is where all the guidance happens and the measurement will vary the angle depending on the ring size, not to mention the crank/ring clearance issue of changing from small to large ring. Most of the challenges I have had with FD is adjustment from small to large ring without overshoot or interference with the crank arm. Large to small is simply a limit screw adjustment.

Now that I think about it. If the chain line is set up correctly, angling the FD relative to the ring plane, shouldn't be required.