Help me identify downtube shifter boss type I think I received this frame with standard Shimano cable stops, but they don't seem to fit. Also, I couldn't found this shape of downtube bosses anywhere.
The problem seems to be with the non-rectangular shape of the &quot;base&quot; part of the bosses. I can't fit the cable stop over the base, there's a huge gap and the stop can rotate around.
EDIT: I've shown the frame to a local framebuilder who's been in the business since early 90's and he said he's never seen this type before.
Those look like standard shimano-style downtube shifter bosses.  You would need some downtube shifter levers ending up something like this:

If you want to use brifters (integrated levers) then you need a pair of bosses to stop the outer, which look something like this:

With these, the outer cable continues up to the levers either in a graceful arc, or to the bars so it can pass under the bartape.