Help ID Campagnolo Cranks
 

I have a set of Campy cranks (see pictures) that I just took off a bike with the word "Strada" and the number 170 engraved on the inside of each crank arm. Obviously "Strada" means "road" in Italian, and 170 refers to the crankarm length, but also, on the drive side there is a "0" surrounded by a circle, and on the NDS, a "4" surrounded by a circle. What does this indicate and does it mean that they are a mismatched set? I'm assuming these are Record, Nuovo Record or Super Record. I've never known how to tell the difference. The chainrings that I had on them were Campy but probably not the original ones, so not sure if they would help to ID the set. Any ideas about what it's worth?

Thanks.

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The crank arms are Record, it's the webbed (Nuovo) or non-webbed (Super) rings that makes them NR or SR. The 0 and 4 are dates, 1980 and 1984. Not unusual to have mixed dates on one set, but 4 years apart? Maybe not from the factory that way.

39

I see. In that case it is a Super Record crankset, since the chainrings are not of the webbed kind. It is interesting that they would be 4 years apart, thanks for that insight.

Yes, they are mismatched, and the drive side has the dreaded stress fracture. Looks too deep to easily rectify.

I would go after it with a "chainsaw" file. A nuisance, they do grow but I have never seen a crank catastrophically fail there, I have seen them fail at the pedal eye and at about the base of the shield logo but only then where the cranks have shown foot / ankle rub. It was explained to me by a metallurgist the why on that but not recently enough for me to restate it faithfully. Part of it is a conjecture on the alloy Campagnolo used,(which may of course changed over time).

For what its worth the very first generation Campagnolo Record cranks were raw and the area of the common stress riser zone was machined well back, it was surprising to see. Why they dropped that I have no idea other than it being possibly harder to machine. The very last versions (indeed Super Record as the "nuovo" record cranks were gone, had not machined flute on the arm, and the logo was laser etched not stamped, also the backside of the spider to arm region was very different with much more material and probably CNC machining.

Uh, whoa.

I will take a closer look at the crank. Thank you. FWIW, I rode this crank for many years and was saving it for building up a classic Italian show-bike someday. I'm glad that I never thought to sell it or I wouldn't be able to live with myself if I gave someone a component that might fail and injure them. Maybe I will hang the crank on the wall and admire its beauty instead.

It is more correctly a Record crank with Super Record rings.

Well, you could then get matching date codes then. The drive side arm is quite beat up on the back side. File the crack, what we see is the black line at the junction of one of the spider arms and the crank arm. File it, and dress it smooth. That is why I suggested a chainsaw file as they are quite fine cutting. These cracks don't cause catastrophic failure, they can render the part a paper weight, if its failure you are worried about the gouges on the back of the arm are the stress risers.

I'm probably stating the obvious here, but given the mismatched date codes on the arms, the rings may be different still and not correspond to either arm.

For sure.

There is enough contact with the front derailleur cage scratching the right arm to make using them Questionable.

Should we start another thread or can we start posting pictures of filed cracks here? I would be very interested in seeing what you all have done.

Cracking on similar fluted style cranks from the 70's and 80's are more common that most People think. There was a batch of Mavic model 630 road cranks that had the same problem of cracking at the base of the spider, next to the crank arm. Supposedly, the cracking problems with the Campagnolo cranksets were so well known back then that Stronglight actually publicized their using a "softer" (as opposed to brittle?) aluminum alloy for their model 107 and 106 cranks in the 80's to avoid cracking problems.
As for crack mitigation/prevention, I thing a small fine rat tail round file will work then it should be followed up with a finer jewelers file, then polishing with metal polish so there will be no grain or filing nicks in the surface of the aluminum to propagate a new crack. You can't just file it and expect to avoid cracking.

I agree, how about a picture of the final product.