The bikes with gear weigh about 40kg (~88lbs) each, loaded but with unfilled water bottles and no food.

As to the second question, the weather has been bad enough in Britain for us to avoid camping for the very reason you identify -- packing up everything wet, and then unpacking it wet that night. But we have ridden through some wet days, such as yesterday in Holland, and the gear inside has remained dry -- packs and handlebar bags.

On the ferry leaving Newcastle, I though we would be leaving the wet behind. The ship's captain avoided one storm, and headed for blue skies and high, light cloud. But when we woke up next morning and peeked outside, it was... raining again, and didn't stop until we had ridden almost all the way into Amsterdam. Then it started again last night.