To jwsknk — You are correct; Dr. Bob was known for his ultra-endurance rides like RAAM but you could always count on seeing him and his family/team riding the ride. I believe it was their custom to do the ride twice — starting in the end town and then riding the route in reverse from east to west (generally meeting the ride on either Monday or Tuesday) and then upon reaching the start town turning around and playing “catch-up”, eventually overtaking and passing the ride again by Thursday before continuing on to the end point.
Looking back at my OP, perhaps “famous” wasn’t exactly the correct word and I’m thinking I should have said “well-known”. But I
thinking of those people like ‘Banana Man’, or Ed Gelles of Knoxville with his single-speed 1940s Schwinn and his “Gears Are For Wimps”-emblazoned shirt. They are not become “famous” as we normally use the word, but are/were still an iconic and prominent part of RAGBRAI.
And for michrider — I was considering only riding participants, not long-time vendors, support staff, or entertainers (that might have become the subject of a second thread, in fact). Otherwise you better believe that “Mr. Pork Chop” would have been there, as well as Lorin Christiansen (the original ‘Chris’ of “Chris’ Cakes”) and the Iowa State Patrol officer who could be depended upon to show up at least one day along the route directing traffic while wearing a huge red clown’s nose, just to name a couple of others.