Same deal where I work. We can enter as steps, cycling minutes (147steps/min) or vigorous activity minutes (211steps/min)
For my commute my average solo speed as reported by computer is almost always 20mph+ (I live in flatland)
The annoying thing is if you enter as cycling or vigorous activity the slower I ride the more steps I get!
I did note that the conversion table indicates that cycling at 14-16mph is 250 steps per minute.
This table:
http://www.healthline.com/hlbook/dia...-caloric-goals suggests that cycling at 20mph is 1.8x the metabolic equivalent as at 15mph. So 250x1.8=450 steps/min
(I was told that the idea for activity matching was equivalent calories burned, or metabolic rate, not equivalent miles covered or actual physical steps or pedal strokes)
Last year I entered my cycling converted at 400 steps/min when the cycle computer noted 20mph average and entered my data as steps. With 200mi/wk of cycling I got flagged my the admin as an 2x outlier and debated with them what I should enter and just settled on vigorous activity at 211steps/min so as not to cause controversy.