Originally Posted by
Iride01
But you aren't saying to disregard the seat tube length or nominal size cm or S/M/L.........right?
I can imagine some with really long arms and torsos with short legs not being able to reach the pedals properly on some of the old bikes with horizontal top tube that increase stack by simply increasing the head tube and seat tube length. Even maybe some newer geometry bikes to with sloped top tubes.
For horizontal top tubes, look at standover height. If you have that, seat tube length should be fine, but if it's close you're getting into the issue that you might not have the saddle-bar drop you want. So yes, you want to check stack height and I am saying to disregard seat tube based and S/M/L sizing, the former because it's outdated and the latter because it's imprecise.