There is no such thing as dry miles in Eire and suffice it to say, as much as I wanted to avoid rain, it just hasn't beenn possible. My C5 has been caught in several downpours coming to and from work, even on one occassion from the dealer. Never once gave me a problem and I was worried as you know many of the parts are just openly exposed. The bike is like a tank, takes a licking and keeps on rolling.
Some people use pressure hoses from your do it yourself car washes.... avoid doing this, particular those of you with tubless tires. Very dangerous. As the lads said, use common sense, you'll be grand. When in doubt, wash by hand and only use a low powered hose for the bits of the frame that are clear of any important electric bits.
Hope this helps.