I'm very happy with all of the features of a new Delphi 6.0 which I bought to put on a Specialized Roubaix. A primary reason for choosing it was the "% grade" function. After several rides, however, I have been unable get a % grade reading after returning home and recording stats in my ride log. (I've read and re-read the somewhat-ambiguous manual, to no avail...)

There's a mile-long climb I've been doing to check the Delphi's accuracy. The climb's altitude goes from about 400 ft. to 700 ft., and the grade is is between 6% and 8% with the last quarter mile at 12%. I know this because of the stats on my Trek, which uses a Vetta 100A; these figures check out with a topo map, too.

I must be doing something wrong in my set up, but I can't figure it out. I'm THINK that I'm calibrating everything according to the manual:
I've stored my home attitude (423 ft.). Before each ride, I have calibrated the Delphi to the stored number by a "press & hold" of the Option key. Then I set the screen to show Distance on the bottom line, and take off on the ride. What is my 62-year-old brain doing wrong?

Hoping for some advice from a fellow-Delphi 6 user...