If it's easy to do, I try to avoid riding for about 15 minutes after it starts raining. When the road first gets wet I find it slick but after all the oil and dust and whatever is lifted off the pavement it seems to be a lot better. If I can't avoid it or it starts raining while I'm already out there, then I take it easy and leave lots of room in front of me. I always take corners pretty slow in the rain - never know what's hiding under even the thinnest sheet of water...
2009 KLR650: Workhorse, dirt pig, mule, traveller. Makes me smile every ride.
2012 Versys 650: Jumpy, nimble, eager, traveller. Makes me laugh maniacally.