bike tour?

I was planning on going to Cologne tomorrow for Karnival, but I think it will impossible to get cheap accomodations. So instead I am considering a short tour along the Rhein river starting at the Lake of Constance. The weather is supposed to be great for the next week, so it should be feasible. I have everything ready, so we'll see what happens tomorrow. My friends are all gone, and my parents won't be here to visit for almost 2 weeks, so I have plenty of time.