21F this morning, clear, calm. Changed out my toe clip pedals for mountain bike platforms. Clips were becoming cumbersome in the dark and in traffic. Much more comfortable now since I switched to hiking boots and merino socks for the winter. Last nights commute was superb, and I remembered to slow down on the bridges to about 8 mph. I glided over the black ice with ease as the studs did their job. I felt just a slight shimmy as the studs started to stick.