If you are riding a faired motorcycle vs the assumed unfaired motorcycle the water consumption numbers will have no co-relation to reality. Behind a sport tourers fairing and windshield we have less area exposed to the wind than than his calculations require.
Because of the many configurations of fairings & windscreens on different bikes and the resulting differences in air flow characteristics, the author almost had to use an unfaired bike as an example.
Secondly, the assumption is also made that the rider is wearing mesh that does not impede the flow of air across exposed skin.
That pretty much describes my Joe Rocket Phoenix. Yes, technically you can say that the mesh fabric blocks part of air flow but there is still a heck of a lot of evaporative power in what wind does reach you when you're doing 60 to 80 mph, even if you are wearing a T-shirt underneath like I do.
I have no doubt from my own experience riding in the 90s and low 100s that at some point I'm cooler wearing my Aerostich and configuring the vents and pockets to scoop air feels cooler but I don't think the difference in liquid intake requirement is nearly as stark as the article portrays and the crossover point is not exactly 93 degrees.
I think it's important not to get lost in the "forest" of details of his calculations. In my mind, the thing to take away from this article is the general principle that at some temperature/humidity combination, evaporation is going to become excessive and become counterproductive (from both a body temp and hydration standpoint). For my area, that temperature seems to be about 95. In others it could be less. It's better to be safe than sorry where heat stroke, dehydration and fatigue are concerned.
Beyond 95 degrees, wearing a mesh jacket feels to me like I'm sitting in front of a hair dryer on high heat. I can literally feel the waves of super hot air coming off the concrete. With my Aerostich on, that is not a problem.
In near 100 degree heat under mesh on long trips I supplement my own sweat production by carrying a liter squirt bottle and wetting my neck gaiter and wicking shirt while riding. This is water that goes to its cooling work instantly and doesn't have to be consumed. A rewetting every 15 or 20 minutes is like riding in air conditioning.
I do the same thing by wetting my T-shirt, but not every 15 or 20 minutes. That frequency would probably be required with a mesh jacket but not with my Darien. A 15 to 20 minute interval to stop and wet down is just not doable when I'm on a LD trip because of the need to make decent daily mileage. This is just one of the reasons I never use my mesh jacket while on a LD trip. I can ride just fine in all temperature ranges with my Darien.
[FONT=&]One of the little tricks I've used to keep cool on those 100F+- days is to pour crushed ice in the pockets of my Darien. Works well to keep the core temp down.
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