TEAMWORK
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If heat is a concern, go for the swamp cooler effect (evaporative cooling). Soak your undershirt in water, put it on, then put on your suit. It will suck heat from your body as it dries (as the water evaporates), cooling you. Same principle as sweating, just cranked way up.Guess you don't ride much in the Valleys. Heatstroke would get you before the crash.
And as temps get really hot, i.e. 100+, you actually are worse off going with mesh or without gear -- exposing your skin to air hotter than your body will just heat your body up more. Better off being closed up in gear with a wet shirt under there, insulated from the extreme heat. Some folks who've done dessert crossings and such in really hot weather advocate filling your pockets with ice, which will melt and keep cooling you. An Aerostich comes in handy here.
I live in Livermore (where it gets hot as hell)... I ride every weekend unless I'm racing... I don't care if it's triple digits, I'm out in my full leathers. Hell, my first race weekend it was 108 degrees in the early afternoon. I did my practice sessions, I raced, and was nowhere near heatstroke. Was out riding the last time we had triple digit temps... kept myself hydrated, and had no issues whatsoever. And it's not like I'm in shape or anything. But the leather insulates against the heat, and I made sure to drink quite a bit of water and gatorade. Is it as much fun as riding in temps in the low 80's? Of course not... but I love riding, and I'm not willing to give up a day's ride just because I'm going to sweat.
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