Coldest I've ridden in is 37F, if I remember right. Froze my lugnuts on a 7 mile ride into work. Had the same problem with gloves as Rob described, and legs were chilled, arms - wasn't terrible, but wasn't comfortable. That day, I only had on chaps, my wool socks, WallyWorld boots(gotta admit, really comfortable, surprisingly enough), LS shirt and undershirt under my leather jacket & a gaiter. Had on my open face helmet w/shield if I remember right.
Went on Lt. Dan's ride this weekend, started out at 30f, but by the time we rode, was up into the high 50's. Had longies, top & bottom, jeans, chaps, Tshirt, leather jacket, wool socks, tube socks & the boots, was very comfortable. Oh, gloves and half-hat too.
I'm like Mike, I'll ride year long if at all possible. Think I need to add a balaclava and the glove thing, and maybe a FF or the like, and should be good to go down to the 30's, maybe 40's. Layers are the key, just haven't figured the layers out quite yet.
I ride an Eliminator
. What you got?