On my recent trip through France, I took my bike and all the gear in two large suitcases (the bike is S&S coupled). When I weighed them at the airline counter, they came to 99 pounds. I was shocked. There was very little inside those cases when I left the hotel, cases and all was certainly no more than 10 pounds.

The bike is between 35 and 40 pounds without racks or gear. So the racks, panniers, and gear ran between 40 and 45 pounds. Either way, it was about 90 pounds plus me (180 pounds) and food and water. I managed it without too much problem, though one day I did have to walk uphill for about a mile to get the top of the second 1000 meter pass I'd cleared that day.

That said, it is always better to carry less weight. One place that I try to save weight is in toiletries. Everything goes into a small plastic bottle or tube; nothing metal except razor blades.

Next time, I'll use lighter tires, too. I got a new pair of Schwalbe's Marathon Plus and found them to be quite heavy. I didn't get any flats but with lighter tires and tire liners I don't get many flats, anyway.

Assume that a few weeks into your trip that you will have a much better idea of what you want to take and how much weight you feel comfortable with. On a ride to Arizona, I came across a German couple touring across the country. They'd been on the road for about 2 months. The man of the couple was pulling a trailer and had a full set of panniers. When I asked him about it, he shrugged and said that he was used to it by now.

Are you aware that there are several couples currently riding bikes around the world that have websites? You don't say where your 1 year tour will be, but you might find those sites valuable:

http://www.cyclingaroundtheworld.nl/index.asp

http://homepage.mac.com/isaetterry/index.html

http://www.erck.org/

http://www.downtheroad.org/

I'd also suggest looking at www.biketouringtips.com for more links.

Ray