If your average cadence is 85, you are probably over 90 most of the time. Slowing down for turns, coasting momentarily, climbing, all that will bring the average down. CDR will tell you that during a race his most frequent cadence is zero, because of the drafting. But when he's pedalling, he'll spin.

Just push a gear that is one lower than you think is "normal" for the speed you are maintaining. You'll be surprised how quickly the lower gear, and higher cadence, becomes the new "normal".