Hi Ikubica:
Thank you for your comment
What we measure is relatively straightforward: the horizontal length from the top of the head tube axis to where it intersects the **effective** seat tube axis. That's the trick, because the ffective seat tube axis is a line out in space which makes it hard to measure with a tape measure.
What we don't do is what a lot of other brands do and that is "dumb down this measurement" by trying to pretend that the axis of the Effective and Actual seat tubes meet in space at a "magically changing saddle height that just happens to correspond also to the stack measurement". Because it doesn't. Unless you are a relatively small person, your saddle height is significantly higher than the stack measurement from the top of your head tube.
Hope that helps clear a few things up!
Dec. 2, 2020, 10:28 a.m. - knollybikes.com
Hi Ikubica: Thank you for your comment What we measure is relatively straightforward: the horizontal length from the top of the head tube axis to where it intersects the **effective** seat tube axis. That's the trick, because the ffective seat tube axis is a line out in space which makes it hard to measure with a tape measure. What we don't do is what a lot of other brands do and that is "dumb down this measurement" by trying to pretend that the axis of the Effective and Actual seat tubes meet in space at a "magically changing saddle height that just happens to correspond also to the stack measurement". Because it doesn't. Unless you are a relatively small person, your saddle height is significantly higher than the stack measurement from the top of your head tube. Hope that helps clear a few things up!