Lets face it, frame size is a variable commodity,
Traditionally, on a conventional horizontal top tube frame, the size is the length of the seat tube, centre to top (British) or centre to centre (Italian) and there's about 2 cm difference in the two measurements.
With modern compact geometry, actual seat tube length is irrelevant so a virtual seat length is sometimes quoted, but (virtual) top tube length is more important.
Many manufacturers sell frames in 2cm increments, 50-52-54 etc, but these numbers bear little resemblance to the length of any actual tubes on the frame.
And others just go for sizing in the small-medium-large way.
So what I am saying is that 2 frames in the same nominal size may actually be completely different in reality.
Lets face it, frame size is a variable commodity,
Traditionally, on a conventional horizontal top tube frame, the size is the length of the seat tube, centre to top (British) or centre to centre (Italian) and there's about 2 cm difference in the two measurements.
With modern compact geometry, actual seat tube length is irrelevant so a virtual seat length is sometimes quoted, but (virtual) top tube length is more important.
Many manufacturers sell frames in 2cm increments, 50-52-54 etc, but these numbers bear little resemblance to the length of any actual tubes on the frame.
And others just go for sizing in the small-medium-large way.
So what I am saying is that 2 frames in the same nominal size may actually be completely different in reality.