I plan to ride this winter EXCEPT during rain and snow. Can anyone recommend a good winter riding suit. I would like for this suit to be big enough so that I can just slide it over my work etire and still keep me nice and warm.
Do what full-time, all-weather riders do. Get an electric jacket liner (goes under your leather) and probably gloves and add a powerlet (BMW plug) to your 'Busa somewhere to drive it -- I put mine on the inner fairing.
Electric gear is thinner, lighter, and more effective than insulation alone. It really, really works well, for the simple reason that it adds heat to your body instead of just blocking the wind and keeping the heat in.
For the cold stuff (down to 12degF so far) the jacket liner keeps your core warm, which generally keeps the legs warm, and the gloves keep your hands useful. The gloves attach to the jacket liner, and the jacket liner plugs into the bike.
The best heated gear for my money is made by Gerbing's (
http://www.gerbing.com). The powerlet kit can be had from Jastek (
http://www.powerletproducts.com) and may be installed such that it isn't especially obvious.
Vests are cheaper, but the higher collar and total arm coverage of a jacket liner are worlds better, and this stuff exists to make you comfortable and safe, after all.
A jacket liner draws between 75 and 80w, and gloves are somwhere around 15w.
You can also add a pants liner for really long rides. With the jacket liner and gloves, the 'Busa's charging system will keep up, with a pants liner you may have to keep the high beam off to avoid draining the battery.