Tuesday, January 29, 2008
Gear in review
So I've been doing a ton of research on the whole learning to survive snowbike adventures thing. What I've found is another complete bike culture. There's lots of info, but I'll try to sort some of it out here.
Starting with clothing.
There are a couple of basic things to remember:
There are four forms of heat loss; radiant, conductive, convective and evaporative.
Regulating your body temperature to control perspiration is critical to staying warm. The body's natural response to overheating is to increase evaporative cooling by perspiring.
Water has a thermal conductivity 23 times greater than air. If your insulating layers are soaked with sweat their conductive heat trasfer rate equals that of water, regardless of what the material is made of.
Convective heat tranfer can be controlled by proper venting of clothing and overlapping layers to prevent drafts. "Breathable" fabrics can not be considered proper venting.
As an example of breathable fabrics, Goretex blocks 97% of evaporative heat transfer, and they consider that breathable. Even that quickly becomes ineffective in below freezing temps as the water molecules quicky freeze and clog the open pores in the fabric.
There are two different clothing theories to look at. They both include a shell layer that blocks the wind and precip, a thermal layer, and a base layer. The difference comes with what you do with that base layer. You can either wick moisture away in an effort to stay dry and warm, or you can trap that moisture with a vapor barrier so it doesn't soak your insulating layer, thus slowing the evaporative heat transfer, and maintaining your conductive heat retention. Your insulating layers are most efficient when dry, therefore as you sweat and soak your insulating layer the insulating properties are slowly lost. So by trapping all that moisture inside your base layer you will stay warm indefinitely, no matter how much time you spend in your clothes their thermal properties stay the same. Therefore you should never get cold providing you have a thermal layer to match the conditions.
I should note, not everybody agrees on the use of vapor barriors. In order for a vapor barrior to be effective, and really one of it's main purposes, is to make you monitor your perspiration and keep it to a minimum. Some people simply produce too much heat to use a vapor barrior without excessive sweat pooling up. The risk then comes with the base layer freezing to the skin if proper thermal layers and levels are not maintained.
The trick with either system is trying to regulate the amount of body heat generated to keep the sweating to a minimum. Just by adding a vapor barrier you increase your thermal insulation quite a bit, its easy to overdress and end up standing in puddles. So far I've found it's gotta be below 20 deg for me to be able to wear a vapor barrier layer without sweating a ton. And unless it's below zero, I'd better not have much of a thermal layer on, even then. I guess I need some more practice adjusting my thermal layers and venting.
This picture shows my current complete clothing sytem for wet and dry weather, good for about temps 55deg down to about -15deg F. Realistically this system is only good for 3-4 hours and then all my thermal layers are soaked and need to be swapped out.
I use medium weight and lightweight Smartwool tops as my base/thermal layer. Wool is an extremely efficient insulator, and with these Smartwool tops the zipper allows venting, they dry very quickly, have very low pack weight and bulk.
I picked up a nice Nike Storm-Fit Jacket this year. It does a real nice job blocking the wind and precip, windproof/waterproof fabric, waterproof zippers, hi-vis orange w/reflective stripes, and adjustable venting too.
I've also got a light insulating pack coat for standing around while not on the bike, but I've yet to use it on a ride.
I start with a set of the old version Desoto five pocket bib shorts. They've got pockets to carry small stuff in during warmer conditions, and they've got a nice light fleece pad in them that keeps things dry and comfortable without getting in the way. Unfortunately they've went and "improved" these shorts with the standard "diaper butt" pad and doubled the price.
I picked up a set of Sporthill XC pants this year as well. Wind proof, water resistant, breathable, thermal, snug fit. Perfect by themselves down to -10.
For colder weather I'll put my Louis Garneau leg warmers under my pants.
Hind Drylete Balaclava : Superlight, versatile piece that I use as a hat or a balaclava. Windproof, water resistant. Good for taking the chill off brisk weather down to about 10 deg.
For colder weather I put my Louis Garneau Power Cap on over my balaclava or switch to my heavier neoprene/brushed fleece balaclava. I might have to try JP's "headband over the nose" sytem to see if I can reduce some fogging.
I've had mixed results using my vented Oakley M frames and vented Oakley snowboard goggles. In calm conditions they both fog/frost up, so I end up riding with no eye protection. In temps below 20 deg I find I have to thaw the condensation off my eyelashes every few minutes becuase they freeze together when I blink. In light windy conditions above 20 degrees the M frames work well, anything colder or windier and I use the the goggles.
All that goes under an oversized helmet cause I'm not less likely to fall in the winter and I don't slow down unless I can't go faster. It also keeps my hats from blowing off and makes a handy spot to attach lights.
Cheapie bar mitts I bought back when I still owned a snowmobile. These things are the bomb, single most effective winter use item I own. Windproof, waterproof, insulated. Ride with no gloves down to 25 degrees, light gloves down to 0, shell mitt takes you wherever you want to go.
$8 knitted wool glove/mitt from Orchelin's farm supply. You know the ones that the mitt part flips back so you can work with your fingers. Preferably long cuff to eliminate drafts. These work great, all sorts of options for venting/temp control. They can be super warm, yet you can get your fingers out quick to open wrapers/zippers/ect. Lots of nose wiping surface. Only downfall is they can absorb alot of water.
$8 shell mitten from Menards. Another good deal, super warm, powder skirt, dumby cord, lightweight, waterproof/windproof. Only downfalls being no removable liner and no nose wiping cloth.
I've tried my $65 snowbarding gloves, lobster mitts, ect. None of that comes close to working as well as the bar mitts and light glove/mitt combo. I might upgrade to a set of Epic Eric's poagies, and maybe a little nicer light glove liner/shell mitt combo, but otherwise my hands are happy.
Last years model Lake MX301 winter cycling boot, one full metric size larger than my standard cycling shoe, studded with sheet metal screws for ice. The standard by which all winter cycling shoes are based and about as good as it gets if you want to keep your clipless petals during winter cycling. Good down to 35 degrees with thin wool socks, 25 degrees with thick wool or polarfleece 300 thermal socks, below that your gonna need toe warmers or something additional to stay warm for more than an hour or two.
I use either Bridgedale heavyweight wool socks or a Polarfleece 300 thermal sock/Fox river wicking sock liner combo. If its below 20 degrees I've been using a grocery bag as a vapor barrier between my liner sock and thermal sock, and Grabber MyCoal adhesive toe warmers. I've been toying with plastic bags as vapor barriors, which is effective, but prone to tearing easily. For prolonged use I think I'll be looking for something a little nicer.
I've tried Hottronics electric footbeds, but the batteries are always dead, the cable's an uncomfortable PITA, and they just never seemed to work all that well. Plus they're heavy.
I also tried some off brand insole warmers, but they wouldn't stay under my toes, and they didn't get all that warm. In the long run you can get a whole winter's worth of Grabber adhesive toe warmers for less than half the price of a set of Hottronics, they stay put, they're easy to pack, you don't have to worry about batteries, and they work. The toe warmers also fit perfectly in a mitten.
Ok, so thats what I'm using currently. For the most part I'm pretty happy with this system. It's all pretty versatile, lightweght, and low bulk. For longer cold exposure all I need to do is add some insulated vapor barrior base layers to the mix like this, or this, to contol the evaporative heat transfer and maintain my clothing's conductive insulation properties. And add another shell/insulating layer over my boots somehow to boost their temp range, like this, with somthing like this, or this.
More to come.