Originally Posted by Hezz

SAB,

The stainless steel vacuum bottle is the only thing that will reliably work in cold tempertures. There are some slim line ones that might fit in a bottle cage but the best bet is to carry a small backpack instead of your camelback. I carry one in winter with an extra fleece layer in case I get a flat and need more insulation while fixing it. Also, the vacuum bottle will work better if it is out of the wind stream in a backpack and is partially heated by your body heat.

It works really well if you wrap the vacuum bottle in your extra clothing layer to keep it's heat in. The best ones to use for cycling are the lightweight ones that are used for mountaineering and don't have any fancy lids or handles. They are much lighter than the typical work lunch variety.

I feel mine full of hot tea and it stays hot for up to three or four hours. I go longer between drinks and then stop and drink a hot cup every 30 - 40 minutes.

It makes a winter ride very nice.