I've never ridden through any of those cities during the week or on a weekend. In St. Louis, traffic is lighter on the weekends. I was asking from a standpoint of trying to get the shortest/fastest route. I could bypass the cities to avoid traffic but that would add miles and I might not save any time overall. For those of you who have done a 50CC, which is better - weekend days or week days?
Jim, you're crossing the entire country. Your departure time will dictate when you hit major cities where most traffic will be. Outside of the major cities, it's I-8/10/12/10, anything can happen, or not happen, on any given day. There is no better, only what's better for you and your route. There are places where you can detour around cities, depending on your route, that make sense. 12 from Baton Routon bypasses New Orleans, for example. Some swear by 8 North around Houston. There are posts about those options here in other 50CC/100CCC threads.
I wouldn't choose to do it Labor Day weekend. Motorhomes and tourons will be out in force. Other than that, it really doesn't matter weekend or weekday, what matters is timing your ride so you avoid rush hour in major cities. Honestly, big cities always have traffic, even on weekends. An unknown to you event can clog things up if you're unlucky. Sports game letting out, etc.
I left San Ysidro at 6 am on a Monday, hit Tucson around noon, but worked thru traffic ok, then I stopped for some sleep just East of San Antonio about 12 hours later, hit the road at 4 am and was thru San Antonio and Houston before any serious traffic. By the time I got to Baton Rouge it was still well before lunch rush and I picked up 12 and continued on to JAX w/o issues. At the time, I would sleep in 3 hour cycles and would be off the bike for 4 hours, sleep for three and be back on the road, well rested. This was not a 50CC ride, but part of a 10/10ths ride.
Figure out your route, then start figuring out when you want to start your ride and when that puts you at the choke points on your route. Heck, you can check traffic for various cities before you do your ride, for the times you expect to be there.