zonatandem

WOOL works!

Black wallnut 

Speaking of heat-sinks how much heat is transferred through the nylon/plastic baseplates of Speedplay?

Kai Winters

I've two pair of cold weather shoes. The first is an old pair, close to twenty years old now, of Sidi Dominators that are 1.5 sizes larger than my normal shoes. I wear a thin pair of cycling socks with a pair of wool socks, weight varies with temp, insulated insoles and neoprene toe covers. This system works well for me until the temp hits 40 and below.

My "cold" winter shoes are a pair of Northwave winter shoes with Gore Tex. They are only 7 years old and work quite well. They too are 1.5 sizes larger than my normal shoes. I use the same sock system as above and use a pair of insulated insoles as well. These require no chemical toe warmers until the temps hit the teens then I use them.

We all have different tolerances, etc. You will have to experiment until you achieve what is comfortable for you.

Before I started using the above systems I used to spray anti perspirant on and between my toes to keep my feet from sweating. This worked very well. I don't need to use the spray anymore.

Good luck and keep us informed on what works for you.

Hypno Toad

I don't have a detailed answer for you. Here are couple stories to think about and might help with this question:

I have a client that use heat-sink methods to cool industrial control cabinets, very effective and they don't use any "coolant" or fans. Just aluminum to draw the heat of of the cabinet.

The plastic in the base of a shoe will offer some insulation, but not much. Think about using a thin piece of plastic to keep the cold out of your house in the winter - it's better the being exposed to the open air, but it wouldn't be much help.

And back to my wife's issue, she rides Shimano shoes with nylon bases and small Crank Bros brass cleats. The brass cleat is enough to pull heat from the sole of her foot right through the nylon. Like I said, you can see the square place on the bottom of her foot, exactly where the cleat mounts to the shoe.

Everybody is different. I run extra hot, I have never had an issue riding clipless pedals, even down to 10F and colder. I also ride down to -20F without covering my face, I get too hot and sweaty. So if you're not having an issue like the OP, I won't spend any time worry about it. However, if you are suffering from cold feet, the heat-sink effect is one area you should consider as you warm up your toes.

Black wallnut 

What I am reading here is you are speculating, not that it's a bad thing. I'll do the same. It is likely the reason her cleat acts as a heat sink has more to due with the mounting method of a plate on the inside of the shoe and two metal screws passing through the cleat, sole, and the plate. The only insulation is the shoe's foot bed insert. Cold feet also seems to be more of a matter of the airy nature of road shoes with air vents in multiple places allowing wind chill to work against you. Three screw cleat mounting systems seem to me to be superior because of slightly less mass of metal. Speedplay pedals are likely even better due to the use of an adapter plate and the fact that the screws are insulated more from the foot than other systems.

That said I also suffer from cold feet even with shoe covers and the use of Speedplay pedals. I've not yet covered the sole vents in my shoes, will do so this winter and report my results if I think of it.

Hypno Toad

This thread was rattling in my head over the weekend, I had these on my mind during my Saturday ride: 45NRTH

This idiot didn't think he needed his shoe covers for 35 miles in 30F weather .... which could have been true if it weren't for the 20 mph headwind on the way home. My little piggies were VERY unhappy all the way home!

It was the bottoms of my feet that were the most uncomfortable, and the shoes I was riding do not have sole vents; going back to the heat-sink theory.

ModeratedUser150120149

Theory only in the scientific sense. It really isn't a "heat sink ". It is a cold sink. Not only a cold sink, but if it has clips, one that has a built in route to move cold into the shoe's interior. To be warm you must block that route, at least.

Inserting some kind of insole will make a huge difference.

venturi95

Energy (heat) travels from high to low, and the heat sink theory works for me. A room temperature thermometer inserted into a glass of near freezing water is not a cold sink, even though it appears to "pull the cold out" of the glass of water. Sorry to get OT and nit-picky.

kgriffioen

these


and then these over top when its really cold

Your problem will be for the most part be solved

ModeratedUser150120149

Maybe the OP will permit some deviation from the thread for this brief digression.

To get a better understanding of cold transfer take a look at the factors involved in cold climate construction. Lots of stuff published about that. I pick that because the info is on a large, easily understood scale. But, the principles involved are the same.

It is a similar situation with cold climate footwear. It has thick soles to keep the cold out. When camping in cold weather to stay warm some type of pad is put on the snow to keep the cold out. Look in any arctic survival manual for the extremes. Different numbers but, again, the principles are the same.

Since the OP says he was riding a road bike I assume he was using some type of foot retention device, like maybe SPD, or similar. What was happening is the cold was penetrating the shoe at its' weakest point, the cleat, and to a lesser extent through the stiff sole. A classic case of cold transfer. If it were heat transfer then the sole would have gained heat.

Keep in mind that "cold" and "heat" are relative terms, not absolute numbers.

Back to the show.

Wanderer

Heat ALWAYS radiates toward cold ------ stop that trip, and the case is solved.

Atakuweh

I'm sorry but I just don't buy this. According to the National Weather Service, at -20F unexposed flesh will begin to develop frostbite in 30 minutes, and that's with no wind. If you're cycling at 15 mph, still assuming no other wind, frostbite will develop in 10 minutes. If you're cycling at 15 mph into a 20 mph wind, it will develop in a mere 5 minutes. So unless you're taking extremely short rides at slow speed with little or no wind, at -20F you're in serious danger of developing frostbite in a very short time.

Hypno Toad

HA! What you 'buy' isn't very relevant. Come for a ride with me and then we can talk.

NWS and other weather organizations are 'protecting' the masses, and these warnings are correct for the masses. They also advise against physical activity when the heat index gets over 100F, but I'm sure you see tons of people around Baltimore out running and biking on those days.

Do you spend any time in sub-zero temps? I've spent my 45 years in Minnesota and been extremely active outdoors throughout the winters. I have a lot of experience and I back it up with research.

You need to considering core body temperature.
Frostbite - Wikipedia, the free encyclopedia

The body's core temperature is the key control in this response, not the skin's temperature. If you keep the core body temperature high by exercising, like you know ....biking, you keep your core hot. This will allow your body to continue to send blood to the skin, in fact, when the core is too hot, it will use the skin to cool the core (just like a hot day).

There was a great PBS show years ago featuring Laird Hamilton in extreme cold conditions with his skin exposed (just wearing board shorts), but he was wearing an electrically heated vest. He was able to stay in the extreme cold for significant time because his core was warm.

Not everyone is the same, not everyone will react the same to these temps. I am only telling you my experience. And to this thread, my threshold for 'cold' is lower than most.

Garmin data from January 8, 2014 near Minneapolis (with a 20 mph head wind):



I had a winter bandanna around my neck, wool skullcap under my helmet and was wearing goggles until they froze over with my sweat (about 5 miles in) and finished the ride with my eyes exposed with frozen tears hanging from my lashes. Example from a 'warmer' day (only -7F):


Edit - one more piece of data, heart monitor: I had a monitor hooked up to Endomondo, for Jan 8: average HR 140 and max 170. Riding in the snow is a lot more work than clear pavement. Therefore, if you see average speed 10 mph as slow and assume low effort... that would be a bad assumption.

Greybeard712

That was pretty clever. Thank you for posting that.
Reading these posts I'm glad I'm not living there (eg. Minnifrozeum). Northern Nevada ain't so bad after all. Of course I haven't ridden in the snow yet. I vaguely remember last year, being bundled up, but I was on a heavy, slow, old ('92) Hard Rock MTB. We'll see what this winter brings on a fast road bike (on black ice?!?).

Jan: 216.....Apr: 207....Jul: 645.....Oct: 535
Feb:- 87....May: 440....Aug: 522....Nov: 214
Mar: 145...Jun: 484.....Sep: 558
2014: 4,053 Miles–258 Days–331 hrs — Weekly Avg: 110

Hypno Toad

As I was biking to work this morning (12F in MPLS), I was reminded of another TV clip that talked about core temp versus skin temp - Mythbusters:


This is about alcohol's effect on the circulation system. In this example, they are drinking alcohol, fooling the body into sending blood to the skin. This warms the skin but reduces the core temp. However, if the core is hot, the body will open capillaries and vent the heat to the cooler skin (the Laird Hamilton clip I can't find)*.

This is part of the OP question about cold feet, be sure your core is warm to keep your feet and hands warm. If the core is not warm enough, the body will restrict blood to the fingers and toes. Therefore, an extra lay, like a vest, on the core is part of keeping your feet warm (or just have a shot of brandy).

Footnote- Mythbusters got greedy, to get their videos on YouTube you must pay for a subscription. I'm cheap and found the free version to post.

*EDIT - While talking with my wife, she let me know it wasn't Laird, it was pro surfer Ken Bradshaw, and it wasn't PBS it was Discovery Channel. Still can't find video from this ... but he's a reference to the experiment:
https://en.wikipedia.org/wiki/Ken_Bradshaw

MidwestKid

As an update, with the short days now my only chance to ride in daylight is on the weekends. This past weekend was nice and I had a chance for a short ride on Sunday when the temperature was around 61 or 62. Being that warm, I decided that I would not need the extra sock, or toe covers, and I would use my old shoes (since I hadn't switched my Speedplay cleats over to my new larger shoes). It was a short ride due to a time constraint, and when I got home my toes were somewhat numb again, but not as bad as the ride on the previous weekend.

This second cold exposure caused more problems to my toes because I have problems with chilblains, or something like that were the small capillaries in my toes apparently break and create painful sore spots. Any exposure to cold after that makes those areas quite painful. I'm now trying hard to keep my feet warm in hopes of recovering from the last exposure.

It might be that I just can't ride when the temperature goes below 60 or 65, but I intend to give it one more shot when it warms up again. We are currently in a cold snap here with temps in the 20's and low 30's. I used to run down into the 20's and might try that again. I'm guessing there is probably more blood circulating through the feet when running than cycling.

Dave

ModeratedUser150120149

Whoa...let's try to get this wagon back to the OP's point. He/she said they had cold, white feet after riding a road bike in cold temperatures and asked what to do about it.

Some talked about the cleats/pedals being a "heat sink". Of course that isn't true. The stuff exterior to the shoes will be at ambient temperature. Assuming the OP is a warm blooded creature the shoe's inside temperature will be warmer than the outside. But the amount of cleat/pedal heating will be insufficient to overcome the cold of the stuff outside. So, add a layer of insulation between the feet and the cold sink and all will be well.

Sorry for my sloppy wording in my previous post. We colloquially talk of cold migrating into a structure. Take a structure that has 8" walls, an outside temperature of -50F and an initial interior temperature of +70F. With a constant BTU input to the structure over time interior temperature will drop. How fast and how far depends mainly on how long the temperature differential exists and the mass of the structure.

Mainframeguy

I experience this too, and the fact it is largely the soles/undersides I think may be a result of riding hard - you are applying pressure at the contact points of the bike, hands, feet and rear are all subject to pressure which could be restricting blood flow and leading to greater cold experience...

I use overshoes, but it needs to be properly cold enough for theme because then my typical experience is that my feet are over-warm if anything (but this is preferable to the pain of cold toes).

Ursa Minor

Keeping the core temp high is important; I once heard the advice that:

"If your feet are cold put a hat on your head"

Charlie

Carbonfiberboy 

You probably have Reynaud's Syndrome:
Raynaud's Disease: MedlinePlus

I ride with two people who have this, though not as bad as you. They say the trick is to never allow your foot temperature to drop. As soon as it does, your blood vessels shut down and the game is on. Therefore wear warm socks, shoe covers (not just toe covers) and even foot warmers as necessary.

These are good foot warmers at a good price:
Amazon.com : HotHands Toe Warmers (40 pairs) : Camping Foot Warmers : Sports & Outdoors

Carbonfiberboy 

You probably have Reynaud's Syndrome:
Raynaud's Disease: MedlinePlus

I ride with two people who have this, though not as bad as you. They say the trick is to never allow your foot temperature to drop. As soon as it does, your blood vessels shut down and the game is on. Therefore wear warm socks, shoe covers (not just toe covers) and even foot warmers as necessary.

These are good foot warmers at a good price:
Amazon.com : HotHands Toe Warmers (40 pairs) : Camping Foot Warmers : Sports & Outdoors

Garfield Cat

Let's get an Eskimo to chime in, including the Igloo and the 8" thick chunk of ice, cut in blocks.

Garfield Cat

I also use Speedplay and the Zero. Perhaps the covers that I keep on all the time may help you, not necessarily for your numbness problems but for other Speedplay usage issues.

Robot Check

Product

MidwestKid

Carbonfiberboy,

Thanks so much for the link. I was not familiar with this condition and thought it was something like chilblains, but may indeed be Raynaud's. The worst thing about it is once it happens, it takes what seems like forever to get over it and during that time the least amount of exposure to cold really makes the affected toes hurt. For example, just driving to work this morning in the cold made my right toe extremely sore and sensitive. I have a space heater blowing on my feet now under my desk and two hours later they are finally starting to feel more normal. I may have some circulation issues that I was not aware of. I did buy a bottle of wine last night in hopes a glass each night might be of some benefit. I take no medications.

I'm already tired of winter and it hasn't even officially arrived. It's just no fun.

Dave

Carbonfiberboy 

Yep, that's it. Try a doc. I think there may be meds available now to at least ease the symptoms.