At the bottom bracket the chainstays are 1.250" in diameter. Astounding.
There is a sizeable indentation for the inner chainring, as well as the stay being squished oval for tire clearance, 25mm may be too big, a 23 an under club member.
Just compressing by hand, well attempting to compress by hand the rear triangle... It is the strongest I have encountered in a steel frame. The bike is made with Truetemper tubing, but no description if it is heat treated.
I will live with an Ultra 6. It is a monster. Neon Pink.