- Neoprene socks + a thin polypropylene sock underneath.
- Try toe warmers! Available at REI as well as many bike shops.
- My current solution is to wear cycling sandals with two medium thick layers of wool socks. Covering the sandals is a not-so-tight waterproof cover I got from a Canadian store. This cover keeps in much of the heat but prevents my feet from getting soaking wet with sweat. I still get cold feet from time to time but I do much better then I used to with normal SPD shoes and tight fitting covers. Here is a link to the covers I'm talking about. I've seen these in Europe and Canada but not in the US yet: http://tinyurl.com/78ymj7
- I was having similar issues. I have found the following works well for me in weather in the 30s: Thick wool socks (I use wool hiking socks), cycling shoes, Pearlizumi Amfib booties (a bit thicker and warmer). If the temps drop into the 20s, I may add my Pearlizumi toe booties underneath the full booties. However, after about an hour and 45 minutes my feet get cold no matter what I am wearing.
- I tend to ride cheapo or flat pedals and will wear sneakers down to around 35F, but when it's really cold, say below 15F, then I want Sorel type boots or mouse boots. I can go for an hour below 5F or so, but then it gets tough. In between, some other variation, maybe work boots. Perhaps I should say I could go, because it's been a while since I've been nutty enough.
- My friend recently solved his cold feet problem inadvertantly throught the wonders of pharmaceuticals... He has some old, minor foot frostbite from years of winter hiking. Those spots bother him, swell and get irritated in the winter. This year one toe became infected so a visit to the MD was necessitated. Beside an antibiotic, he got an "alpha blocker" (brand name of Cardura) that dilates the peripheral vessels and allows blood to circualate and work it's healing powers. Within a day his foot was almost normal and the side benefit was that he now has toasty warm feet when he rides! The drug can cause some lower blood pressure so we bought a BP cuff at CVS to keep on eye on it.
- After years of freezing feet with booties and multiple socks, I switched to a cycling boot. It works like a charm. I don't even wear wool socks. Mine are Lakes with road cleats. My only grief with them is that they let water trickle in during the rain--I just waterproofed them; so, hopefully that's fixed.
I wear two pairs of wool socks. That suffices in all but the coldest weather.
Chemical foot warmers are available, and work for three or four hours. You break a packet inside to start the chemical reaction, and put them inside your shoes. Bruce Ingle, I think, gave me a pair on one particularly cold day, his annual birthday ride. I think he bought them at Home Depot.
The late Sheldon Brown rode the 2004 New Year's Day ride in Shimano SPD sandals -- see this page -- and surprised me with his observation that a major cause of cold feet is constriction of the feet by the shoes, cutting off blood circulation. Sandals don't constrict the feet, and so, counter-intuitively, are much warmer than you would expect. I bought a pair and have had warm feet on days when ice was forming in puddles in the road. (with two pairs of wool socks).
You don't want to get the socks wet, but then wetness isn't usually a problem if the temperature is much below freezing.
I'd suspect that two pairs of wool socks inside Gore-Tex or other breathable but windproof booties inside sandals would be good to even lower temperatures. Aha, now I know what to do with those booties that have been sitting around in my closet, unused because I would have to cut holes in them for the cleats.
The Shimano sandals don't have any materials that soak up water, so they also are good in a warm rain -- wear them without socks and let your feet get wet. Carry socks with you and when you go inside, shake water off the sandals, put on the socks and put the sandals back on.
If not wearing sandals, have a pair of bike shoes a half-size larger than usual, to accommodate the two pairs of socks without constricting your feet.
For really messy conditions, some people go to work boots and flat pedals.
Keeping your legs warm also helps keep the feet warm. I also pull the socks up over my trouser cuffs, if wearing street clothes -- better than any ankle bands to keep the cuffs clear of the bike, and also keeps cold air from getting iside the trouser legs. Today I wore a thick pair of corduroy trousers, and long johns underneath, for the 9 miles each way to and from an appointment. I was comfortable.
Thanks to everyone who replied! I'll post my results here, and to the CRW List.