I do century rides by myself. So I quess you could call them self supported century rides.
I've done 3 total. There is a course marked out by the local club in my area.
I do it to enhance my training. I do it to push my limits and make me stronger. I do it when I see that the weather is going to be beautiful and I want to be outside all day. I don't have to travel anywhere to do it, no extra time involved.
I rearrange my errands and work and obligations so that I can spend the daylight hours on the road. my route goes through little towns that have little convenience stores so that I can refuel. Mr. is home on the weekends and so I try to keep the weekends open for spending time with him, so I do my long rides during the week.
I've gone out a few times to try to ride a century and just wasn't feeling it. The weather wasn't inspiring or the training didn't feel right, or I got a call that I needed to go do something, so those days maybe I only got 50 or 70 miles, but that's still good training.
My question to you is why NOT do a self-supported century ride. The ones that I've done are some of the best riding days of my life.
"Being retired from Biking...isn't that kinda like being retired from recess?" Stephen Colbert asked of Lance Armstrong