My LBS which is about 2 miles from home has a new "Beginner Pace" bike ride Sunday mornings from 9-11. I spoke to them and they said how they ride is determined by who shows up and what type of bikes they're riding. So if a bunch of people show up on carbon road bikes and some of cruisers, they'd split the group and do a faster and a slower ride. So it's fluid. I still haven't made it. I should try one, but 9 a.m. on a Sunday is about the time I'm just getting out of bed!