I really didn't trust my results so I used a spring calculater.
http://www.racingsuspensionproducts....ing%20rate.htm
Outside Dia. 1.5"
coil Diameter.187"
35 active coils
And I got a rate of .40KG/MM which seems more reasonable.
I even tried the original test with the fork cap unscrewed and the outer fork leg all the way down. I still got 2.25 inches for the difference.
I wonder if the spring weakens with age? Cold?