A metric = 100km = 62 miles.
How was the weather? On thursday it was really hot (91) and windy and I did this 52 mile loop in 2:45 minutes, but was in a decent amount of pain the last 15 miles. I did the same ride yesterday with it being 70ish and alot less wind, brought another clif bar, and ended up doing it in 2:15 minutes and felt alot better towards the end.
I notice that I get pain in my legs alot more when I skimp on eating. If I try and eat about every 45 minutes with maybe a clib bar or something like that, I can go all day.