Actually if anything power output might go up if it weren't for dealing with snow/ice/wind. So a stationary bike protected from wind, but kept at lower temperature would probably result in better output as the person pedaling wouldn't overheat as easily. It would actually be interesting to see what the optimum ambient temperature would be.

Probably part of the reason why marathon season is in the fall...

Well, temps haven't dropped into the 30's yet, but windchills have. Today, it was 44 degrees with 20mph winds, yielding a windchill of 36. I wore an UnderArmour coldgear jersey, longsleeve poly midweight jersey, and the Gore Shell. Mixed reviews -- I was definitely warm, but maybe a bit too warm. The UnderArmour was fairly sweaty at the end of my commute. Almost feels like the Gore Shell is trapping a lot of heat which is good and bad. I'll need to experiment with different base layers or less base layers to get the right combination. Definitely think the Gore Shell will be enough to keep me warm down to 35 with one or two base layers.

Just in case anyone is still monitoring this old thread ... Original OP back. Rode in 40 degree weather tonight through a surprise unforecasted downpour. My toes were frozen by the time I arrived home, but my core was warm AND DRY. Not a single drop made it through the Gore Shell!! And, I've found that the UnderArmour coldgear jersey was just trapping in too much heat or was too warm. With two long-sleeve polyester layers underneath the Gore Shell, I'm toasty at 40 degrees (and dry as I found out tonight). Needless to say, I'm extremely happy with the Shell and the layers I'm using under it for my semi-cold rides.

That's good to hear. Now you'll have to work on the toes.

In my experience the last thing you would want is a windproof base layer. The problem is that windproofness is directly opposed to breathability and the inner layers need to be as breathable as possible. The only place you want windproofness is on the outer layer. In order for things to wick vapor they need to be as breathable as possible. With the outer layer you have to strike a compromise to keep a certain amount of cold air out of the warm body layer. But it has to breath enough to let out some body vapor.

Regarding the cold toes: I don't plan on riding in the rain often, so I'll keep a couple of plastic bags with me and insert those between my socks and shoes. Dry toes = warmer toes, I hope.

Regarding layering: After experimenting for the past month in conditions ranging from 40 degrees to 70 degrees, I've concluded that there are two ways for me to layer. The first involves two to three layers of polyester with none of it being windproof. This seems to work down to about 48 degrees. With this approach, my core is not toasty, but I arrive less sweaty and feel that any sweat I'm producing has a chance to evaporate. I feel a lot more wind on my core, and I think the wind is helping remove the sweat (and heat). The second method of layering is to use one or two base layers with my Gore Shell on top. This seems to work well in sub-48 degree temps, especially at night. This keeps my core much warmer probably due to the fact that I am protected from wind, and the heat from my body is trapped within the shell. The flipside is that my base layers are more sweaty, but not too bad as long as I layer appropriately.

I generally agree with jaidog but I would add that you can find jackets that are windproof on the front and not on the back. That allows moisture to escape from the back. When it's below freezing and my wife and I ride it's not uncommon to stop and brush off the frozen moisture off the back of our jackets. Even using the lightest weight windproof (back and front) jacket causes a lot of moisture to remain trapped inside. I also prefer more layers of polyester and hold off any windproofing layer till I really need it.

I think the Bellwether Coldfront jacket I was thinking about getting was windproof on front and not on the back. Would be nice to try that out and compare it to the Gore Shell I ended up with. But, as long as I don't go too heavy underneath the Gore Shell, I seem to be okay. It also has a horizontal zippered vent in the back that I've opened midway through rides where I'm heating up. And, my ride is only an hour each way with showers available in both directions. So, if I work up a little too much sweat, it's not a big deal. Also, as I found out first-hand, the Gore Shell is very waterproof, and I don't think the Coldfront is, making the Gore Shell somewhat more versatile.

Not sure what shell you have, but a few are designed so that their pockets double as vents. If you're still having evaporation issues that might be worth a shot.

Hope you're enjoying the warm weather--40's here this morning.

The shell I have has only one pocket and it is in the back. As you stated, this pocket doubles as a vent, and I am opening it more often now that I'm building up some heat. I suppose it helps, but a jacket that is breathable across the entire backside would be better at releasing heat. Little odd that my shell has just this single pocket. I would have expected more.

That is weird, but i guess that's what you get for $50 gore.

Jackets typically have fewer pockets than jerseys. Usually one in the rear. Some have side pockets or a chest pocket. If you need to carry more stuff you can use a winter weight long sleeve cycling jersey as a middle layer. The jacket will need to be a little loose for this.

I'd do the jersey and a fitting shell. You can unzip the shell as you get hot.

Or get a nice base layer, and wear a summer jersey over it and use a shell. I'm a big fan of wind blocking layers. I also tend to get cold rather than hot, so....

My Capo shell as no pockets. You use your jersey pockets and skip them on the shell so it can be as light and foldable as posible.

I would agree. Wind proofing is the last layer.

According to my personal experience, power and speed start to fall off at around 45-50 degrees. At around 25 degrees F, I notice my pedal stroke becomes less smooth, whether from the abundant clothing or something else (frozen brain stem?) I am not sure, but my legs definitely feel clunkier. Power continues to slowly fall off as temps drop till someplace in the lower single digits (F) when it starts to hurt to breath. That's the coldest I have ridden. To me, 15F or below is cold.

BL