,,,There was a decades old thread where T-Mar stated this model was made from hi-tensile steel. Although picking it up, it weighs no more than a Cr-moly frameset. He also claimed if it has a "Thun" crankset, run away and not buy it, as it required a special tool to extract. This isn't true, as I was able to pull the crankarms off with a standard Park extractor, and the BB came off with standard cup tools too. Hmmm.....The BB cups are Italian-threaded, and Japanese-made....Does anyone know anything about this model? Is it true it's made from Hi-ten steel? The 3 main frame tubes' mid section are oval. And the seat tube is 26.4mm at the post...
Someone has a tendancy for hyperbole! I'm pretty sure that I haven't been on the forum for even a single decade and that post was only 15 months ago, not decades. I never said that Thun crankarms require a special tool for extraction. They use a standard extractor, as you have found out. What I stated was that the Thun (Germany) bottom bracket requires special tools. You don't have this bottom bracket. Yours has "Japanese-made" cups. It appears that Benotto spec'd a different bottom bracket or requested Thun to supply a different bottom bracket, probably due to original concerns with the standard/traditional Thun bottom bracket.
While I did say that I would walk away (not run away) from a Benotto Triathlon with a Thun crankset, that is on the premise that it a Thun crankset (i.e. crankarms plus bottom bracket) and not just Thun crankarms, as on your model.
As for the tubing, it is hi-tensile steel, at least according to the Benotto literature of the period. A 26.4mm post is not outside the range of a lightweight hi-tensile steel for the period. Furthermore, if they had used CrMo or some other higher grade alloy it would be atypical for the marketers not to insist on a tubing decal to proclaim the fact.