Is is possible to calculate stack and reach for framesize 63?
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Yes! Well, sorta. You can get an approximation using.... ~~trigonometry~~
In order to get an accurate reading, you'll need to divide the frame up into right triangles. We'll assume that the top tube is horizontal, parallel to the ground. This makes everything much easier because you automatically get right angles. However, many bikes will have sloping top tubes, which complicates the work. The first step therefore is to determine what slope the top tube has. For this particular example, the chart gives measurements that strongly suggest the top tube is horizontal, or even downward sloping, so this method is likely viable, but double check anyways.
We want to find the stack height, which is length l.
Now calculating the reach is easy. We know the height of the stack is 60.25cm, which is one side of a right triangle with a hypotenuse of 63cm. Knowing this you can use the Pythagorean theorem to determine the remaining side, a segment of the top tube is 18.41cm. We also know the full length of the top tube is 59cm, so the remaining segment must be 59cm - 18.41cm = 40.59cm. And that's your reach!
Hope this helps, and hope my math isn't too bad here!
This calculator here http://bikegeo.muha.cc/ may be helpful. It looks as though it's meant to calculate geometry changes resulting from a fork swap, but it does give you stack and reach.