The are both very early builds, mine the first delivered to Albuquerque.

Guys, guys,
You're all putting your finger in the air in the hope you can detect the direction in which the wind is blowing.
Not good as you all know, if you want to determine accurately the direction in which the wind is blowing you need a weathervane or a wind direction sensing measuring device.
All of the responses to this post are reminiscent of the wind direction scenario above.
Just how long is a piece of string, there needs to be accurate and determined diagnosis of this issue before we get any where near to a solution of the cause. Stabbing continually in the dark will lead to endless paths to nowhere, excessive cost through diagnosis by substitution not to mention the terrible amount of time wasted.
Start with the basics, look at the handbook, first point to note is that they inform you after riding for one hour let the machine cool down for while before the next hour of riding.
If this unavoidable i.e. you must ride in excess of 4 hours, then one must rethink or modify the cooling system to cope with riding for this amount of time. Consider high mount radiators, larger volume radiators, more fans or higher volume vans, changing the sensors for the fan to allow them to kick in sooner and run for longer. Give your machine a chance to survive the rigours you are putting it through, it is after all just a machine, and like all machines has limitations to which we take or push it to.

GMFAHFR