I rode in rain for the first time yesterday. Before that I had been through heavy fog and some light sprinkling, but no real rain. As I was getting ready to leave work the sky turned black and the wind picked up, I knew I was in for an experience. It started pouring down and just got worse, strong wind and heavy rain with thunder and lightning. I took curves carefully, concerned about the slick road, but the bike didn't really have any trouble with traction. I was very pleased with that. By far the worst thing was visibility, that was unnerving. As long as I was moving it was mostly OK, but every stop it would start to fog. Ultimately I just took it slow and was lucky that it didn't last long.
The wife had a good laugh, after I got home OK. My pants (just khakis) were soaked, so my boots were wet inside, and my jacket only kept some water off. Of course this happened 2 days before my new jacket and pants that actually have waterproof liners arrive.
The bike is a 2005 F650GS with Metzeler Tourance tires. I am a 30 year old n00b and have been riding to work (just 10 miles each way) nearly every day other than rainy ones since I got it the end of August last year.