My wife and I live on Oahu. I do a lot of interisland work so we are both in and out a lot. If you are going to rent and ride on a Saturday there is a group (Windward HOG) that meets on Saturday ON Sunday there are many other groups that ride. It is great fun to get in with a local group and check out the local scene. It is common to meet and do a "circle island" tour it is about 110 miles and takes three or four hours depnding on what you stop to see. Where are you planing to rent from? Cycle city is about a mile and a half from the airport and we live about another mile from there.
Have you been here before? What else are you interested in seeing?
My wife is retired military (navy) and goes to the base all the time. Maybe we could meet and go for a ride together.