60s crankset identification
 

This came on a Chiorda, I believe from the 60s
I was not able to find it online.
I am sure a lot of you guys have knowledge about it and can help.
Thank you.

https://cimg2.ibsrv.net/gimg/bikefor...8dcd3ffecd.jpg
https://cimg3.ibsrv.net/gimg/bikefor...2f598d74d6.jpg
https://cimg4.ibsrv.net/gimg/bikefor...22af86f274.jpg
https://cimg5.ibsrv.net/gimg/bikefor...9303697dc1.jpg

Thun. Chiordas and others I've seen from the era had them.

Is it an urban legend that low-end Chiordas were made with prison labor? I've heard the story but I don't necessarily believe it.
Anyway if true, this could be one of those.

A Thun BB isn't the worst thing possible, but it ain't great. And with that bottom bracket shell, you can't easily upgrade to a proper bearing style either, this frame is stuck with it.

Apologies if this bike has sentimental value, but I would look for a more worthy bike to spend your time on. But I'm a notorious bike snob, feel free to ignore me.

Girardengo 62 to 64, so says the net.

I disagree, at least in the case of one Chiorda bike I worked on. Got this as a carcass missing parts and built it up as an MTB for my then-girlfriend, now wife. The BB shell was threaded Italian--with new looking white paint that had never had cups screwed in--so I only needed Italian cups to be able to install this Stronglight 99 crankset.
https://cimg5.ibsrv.net/gimg/bikefor...88c542213d.jpg

Cool! Sorry for the misinformation. It's been 40 years since I worked on a Thun, I thought they had larger BB shell than Italian. Good to know.
SL 99 is a great choice, period-correct and just an excellent crankset.

This all seems to raise the question as to what the cups for this setup look like.

I imagine the bearings sit deep in the cups, and that the cups could be Italian-threaded.
But somehow I'm having trouble imagining a normal-sized fixed-cup flange with wrench flats.

On the one I had--and presumably on the rest of them--it's a pair of unthreaded metal bowls with flanges like smaller versions of #64 or #66 cups for Ashtabula cranks, as below. They just pop into the BB shell and the rest of the bearing assembly gets installed normally. Not a bad setup, but one that is usually found on lower end Euro stuff; Chiorda, Crescent, Kalkoff, etc.
https://m.media-amazon.com/images/I/...1000_QL80_.jpg

I was shocked when I saw it at first, taking apart a dirty, greasy BB only to discover pristine white-painted (frame color) threads in there that just had to fit a standard part. Went and fetched a pair of Italian threaded cups out of the parts drawer and...bingo!