My motivation to cycle is to increase my overall fitness and feel better, etc...
That said, when riding I'm not really sure that I think about anything. I might make a goal to try to beat my personal best before the ride, but won't really think about it during the actual ride. Seems like I just get into the zen of it and the miles just fly by.
For me, cycling is not just a physical activity but also a way to shut off the everyday stresses of life. A way refresh myself mentally and relieve some bulid up stress.
It has often happend that a little while after a ride the answer to a problem, or question, that I've been mulling will just seem to present itself to me.