My bicycle has presta valves. When I measure tire pressure or pump up tires, some air escapes. I doubt that I could keep tire pressure uniform.
I don't pump up my bicycle tires on the day of a measurement, because compressing air heats it and the tires might loose pressure as they cool. Should I be concerned about this?
I have measured calibration courses when the temperature was significantly colder than 68 degrees F. You can adjust for the difference in temperature.
My calibration courses have always been within 2 miles of the race start or finish. I worry that my bicycle tire pressure would change, if I carried my bicycle far in a car.
Dale Summers