And from Chicago Bike Winter -- Tips for Winter Biking Winter biking essentials: * Willingness * Waterproof, wind proof outer jacket (does not need to be insulated--you'll generate plenty of warmth) * Warm, waterproof glove/mitten combos that do not compromise your dexterity * Warm, waterproof shoe/boots with warm socks and room for toe wiggling * Warm, but thin head covering that will fit under your helmet and protect your ears * Wicking base layers, like silk or synthetics * Weekly chain lubing * Worn brake pad replacement * White headlight, red backlight and reflective tape. (OK, folks get by without these, but I think they help a lot with visibility) This I relate more to from my experience though I must admit the cold I have seen even in Germany is not as bad as Chicago's winter. Mainly I give this for those truly interested in being safe in the extremes. Layering of clothes is important if you are doing physical work in cold or hot. I did not strip down to ride in thew heat of Arizona but used wool jersey and a thin long sleeve shirt over. The helmet is shade. For cold you need more layers but wool could be the close to skin layer as it wicks moisture away and allows you to maintain body heat more easily. Same for hot. I do love my out doors and can be comfortable in a variety of conditions and would not dream of not getting out in the elements just because some small discomfort is involved.