Interesting thread.

I'm 23, about 18 years of riding of mountain bikes during the summer. Picked up a road bike last week, and have been riding a lot. 04 Fuji Newest

In my 25 mile ride I can average 18 mph pretty steadly. Oddly, 19 mph for a bit, and 20 mph for short intervals. 20 mph seems 10x harder than 18 mph. 22 or so plus for very short bursts.