Originally Posted by
ridelikeaturtle
I don't know what kind of mathematics you guys are using, but even if you're talking miles (not kilometers), then 7hrs on the bike at 14mph just about gets your 100 done (98) - so starting at 7am, with 1hr of goofing around, you're done by 3pm. More goofing around, 4pm. Unless you're doing this in the dead of winter, it shouldn't be anywhere near getting dark.
Does everybody stop for a 2hr lunch? How is it taking 10hrs to go 100mi, w/o a mechanical problem?
I'm not fast on a bike. Maybe I just eat fast?
Yes, finishing around 3 is quite realistic. Your op had them starting at 7 and finishing around noon, and that's 5 hours. I don't know anyone who would consider 3 pm to be around noon.
Like I said, I rode 33 solo centuries (actually, the longest ride was 168 miles) last year. Since I don't do these in the winter, this means about two a week during the summer. In order to keep it interesting, I tend to take breaks to do something fun. I did one last year in just about 6 hours actual clock time, but it really isn't much fun.
OP is going to want to enjoy the ride, I assume, so taking a few leisurely breaks seems reasonable.