Measuring the Inseam Length
Start by taking a large carpenters square and having the rider stand against a flat wall with their feet about pedal-length apart with their shoes off. Give the rider the square and instruct them to place it between their legs and pull it upwards until it rests against the pelvic arch in the groin. Make sure that they are holding the square flat against the wall, and against the pelvic arch at the same time to ensure that the tip fo the square is horizontal to the ground. Take the measurement from the top of the square to the ground in millimeters (not centimeters).
Measuring the Torso
With the square still between the riders legs and flat against the wall, still resting on the pelvic arch, measure from the top of the square up to the suprasternal notch (the soft leshy indentation at the center of the base of the neck.
Measuring the Arm Length
The arm length measurement goes from the end of the clavicle to the outer fold of the wrist with the arm outstretched. To find the end of the clavicle, feel the bone through the person’s flesh on the top of the shoulder. When you find it, follow it out toward the arm, where the arm and the shoulder meet, there will be an indentation, mark that measure to the “outer fold of the wrist”, which can be found by asking (with the person arm still outstretched, palm down) to fold there hand upwards. Take the outermost fold of the wrist as the end of your measurements. ARM STRAIGHT!
