Last night was interesting. I decided to climb up Edge Hill between work and home. It adds 15 miles to the distance and takes me up an 18% hill and down a 16%. The way up Sun Rising Hill is zig zaggy and the drop down is more-or-less straight. Climbing at a steady 3 mph ( +/- 0.3 ), I was pedalling at 40 rpm on a 25" gear pulling 260ish Watts. A drip of sweat on my spectacles told me I was starting to work a bit. The drop down the other end got my Garmin Edge recording a max speed of 48.9 mph.