In 1990 I rode an 81 Shovelhead Fatbob to Calif and back from Utah. It was 106F most of the way from Victorville to Mesquite on the way back. I drank a whole gallon of Gatorade and never needed a pee stop. I did stop a couple of times and drenched my levis on the way. That was when gas stations still provided air and water. They dried out in about 10 minutes. Lol.
I use one of those quilted type vests when doing very hot long distance summer riding. You soak it in water and then get a nice evap cooling effect for a while. That type of riding is not fun because once it gets past 9 am or so you constantly are getting hit with big gusty thermals.