A friend of mine and I were driving up Flagstaff road in Boulder to get to a trail up top. Amazingly enough, a lot of people were riding up this behemoth. My friend said that she needed to get back into riding it, and I brought up my lack of a road bike. She said that most people use mountain bikes to get up it, because road bikes don't have low enough gears.

Um, that's a long winded way of saying that on some roads, I guess having three rings is pretty important (for most people). On the other hand, that third ring adds weight, so if you don't need it, it's just more weight to drag around.

How many rings does Lance use?

Ah, google to the rescue. Looks like two.

Lance's chainring