Nah, I never could. I always stop, rest, pee, and refuel about every 3 hours, max. That said, back when I was about the OP's age, I rode STP (a double) at a rolling average of 19.9, though my ET was only a hair under 12 hours. Still, that put me in the first 100 finishers, out of maybe 2000. It was a beautiful day and I had a tailwind the last 30 miles, passed everyone I saw. My MO was ride moderate and grab onto many of the pacelines that passed me, adding 1-2 mph to my solo pace was about perfect, then turn up the heat toward the end if I had the strength. Good tactics can substitute for talent and youth.