Itself, you are referring to a Bellweather jacket. Are you wearing a full wind jacket? Front, back, sleeves, everthing? This may be what's causing you to sweat. I've found that windfront is best and breathable out the back.

And be sure to dress for the 15 degree (or 25 or whatever works for you) rule. Dress appropriately for the warmth your body will be creating 15-20 mins into the ride. If you start with too many layers, you'll sweat and then wet clothing won't keep you warm -- even if it's wool.

Are you on a recumbent tandem? You may need to concentrate on windfront tights. Aren't your legs more exposed in some ways? I'm assuming that recumbents place different parts of the body out in the wind that a DF frame would. And a non-breathable jacket back might be even worse for sweating. Just guessing . . .