What makes a great day on the bike?

Being on the bike makes most any day a good day.

What's it take for a great day?

Everything comes together. I get on the bike and nothing aches. In the middle of the ride the legs don't feel the effort, the breathing seems easy. The focus stays completely in the moment with all senses engaged. No wandering off thinking about the to do list. Carving, sweeping, dropping in, rising up, perfect balance. Flow.