If your LBS has a rack that'll fit your bike, to carry one change of clothing and a toothbrush, you can do a credit card tour. Shorts will dry bungied to a rack if you rearrange them once or twice during the day. Provided it's not raining of course and depending on just how light you're prepared to travel.
(disclaimer: I'm not one to travel light and it's been 15 years since I did a solo tour on any kind of two-wheeler, 25 years since I've done it on a bicycle)