The left side is the easiest for them to see you on and to pull over to. Three of them start their day at different times and go until full, take the people to the overnight then circle back. They will drop off riders in the pass through towns only for mechanical issues, otherwise you are on until full. So in the towns there is a chance to find them near the bike shop local. The bikes on the road with no one around> if they have a ribbon on them the rider has been picked up already.