full leathers for winter riding...does it work?

[misterprofessionality]

I think leather does a really good job of
a) Crash protection (but needs armour too, and some new textiles beat it)
b) Wind protection
But is not quite so good at
c) Protection from cold.
Yes, it does protect marginally from the cold. It is not so good when unlined, but it's better than an unlined textile suit. So the "warmth" felt from leather is all in the "protection from the wind" and the warm layers under the leather.
Just my experience here in England.
As I've said, I've a medical problem with "cold" and rather than put on layer upon uncomfortable layer, I use an outer jacket (either leather or textile - I have both) with a thin, heated jacket under. Lined leather trousers with long-johns under are good for legs, and the BMW cylinders take care of my feet!! A one piece rain oversuit affords extra warmth via draught-proofing when on a long, cold ride.

you hit it on the head, that's exactly what i wanted it for. my strategy in the cold has always been combining a dense windbreak outer layer with an effective air gap underneath. this is the basic principle of insulation on a motorcycle. the leather suit works as the ultimate full-body wind break. when combined with a down layer underneath, you have a full body air gap. boom. bubble of warmth.

The final nail to my leathers came when the so called "water resistant" leather was no longer water resistant. The gear became heavy, smelly, cold, crusty (when dried), and just generally sad.

this is what eventually happened to my old leather jacket. rain eventually does it in. the good news is that the weather patterns down here are such that it rains very little during the cold months. it DOES rain, but i actually can't remember the last time i got caught in the rain when it was also cold. i have a lot of confidence that this suit will very seldom ever get wet. that said, it probably will wear out faster than a quality suit, but i paid so little for it, it's a worthwhile purchase. i can't even buy a good winter jacket for what i paid for this suit.