Base layers for cold rides?
With the weather getting colder, I figured I'd ask to see what folks do for cold rides. I commute about 25 miles RT each day, and it's starting to drop into the 20s and 30s in the morning. My problem is that if I bundle up too much, I need to stop at least once to peel off layers. I've tried the Uniqlo heat tech tops, but it's hard to tell if they really help as they're so thin.
What do others do?
= new reply since forum marked as read
So, while I can't speak directly to the specific differences with cycling, I walk hills so I do build up some sweat even just walking. So for me, a breathable technical dual-ply first layer that wicks and a minimum of one fleece (or a second one if there is wind or near zero temps) and a wind-proof layer or goretex depending on precipitation. A scarf that can be pulled over my face, an ear-covering headband and a thick knit under-glove with a pair of deerskin-fleece mittens on the coldest days. I usually wear my winter-proof reflective bill Nike baseball cap under the headband as the bill keeps a lot of icy snow and wind out of my eyes. I'd bet both of those issues are important for you on a bike. I wear wool tights under my pants on coldest days and that seems to suffice.
You may not be experiencing the same extremes, but a single layer fleece over a technical wicking layer ought to work. Add a windproof jacket if windy or an insulated vest otherwise. 
I'll be curious about what more specific advice you get to the contrary...
