Originally Posted by Maelochs

For you: https://www.competitivecyclist.com/S...latorBike.jsp?

For your bike: "Reach" usually refers to a very specific measurement---which I might not understand or describe properly. I believe that it you draw a horizontal like from the top center of the head tube (the almost vertical tube with the fork sticking out the bottom and the stem/bars on top)and a vertical line rising up from the center of the bottom bracket (where the pedals attach) the length from the center of the top of the head tube along that horizontal line to the intersection with the vertical line is "reach."

The stem is not included.

Best way to measure it might involve something like a light piece of lumber or something, which you can stand up from the bottom bracket and tie to the frame Make sure it is perpendicular to the ground ... take another piece, or a tape measure, and run it from the center bolt on top of the stem to the upright board, and use the protractor or triangle to ensure another right angle.

I have a bunch of different sized frames and even on my 61 cm the reach is under 400 mm. For my two 56s the reach is 385-395. I don't see an accurate reach of 420 mm on qa 56-cm frame (nominal 56-cm top tube.) Make sure you measure vertically from the BB and horizontally-Not along the possibly sloping top tube--to the center of the stem-bolt at the head-tube end, not the bar end.

I have a bunch of fit diagrams and could attach one but I am late for work already. Will try to get back later.