100 mi ride is a piece of cake with a well designed, comfortable bike. Mine averages 25mph depending on terrain, sometimes more sometimes less. I ride routinely to a town 25mi distant when R&Ding a bike. One hour non stop, off the bike for 15min for a rest and look over and then back home. Would be no problem to do this in 4 sessions. You have to have a bike designed for traveling. Comfortable seat, bars at the right height etc., and I use a friction lock thumb throttle so relieve hand strain. Traveling long distance with a "style" type bike, I have several, is gonna be limited. Similar to long hours on a sport bike. Can be done but not my many. Ride your bike for an hour non stop if you have a place to do so. At the end of the hour you will begin to see/feel its short comings.