As you’ve all noted, it’s one heck of a hot summer in North America. Now for the folks with the four wheelers that’s no problem ’til the air conditioner quits. But for us riders, heat is assaulting us from all sides- from that on the edge of overheating engine, from the searing air we’re slicing through, and from our own warm blooded bodies, which can’t entirely turn down our cellular furnaces, said heat then trapped by the protective gear we wear.

For riders, surviving heat is about basic physics, or “thermodynamics” for those who like fancier terminology. Our little (or not so little) ol’ bods are programmed to operate at a steady 98.6 degrees F, or 37 on my preferred scale, the Celcius one. Go a couple degrees (Celcius) above or below that and we get sick and die. Hypothermia starts at about 35 degrees C/95 degrees F, but we don’t need to worry about that for a few months at least. What we’re more concerned about is hyperthermia and the heat strokes, illness, and death it can cause. We can tolerate a degree or so C about 37 C, no problem… But a couple degrees above and the judgement and motor skills we need to safely ride deteriorate, and around 40 C we get really sick and without help, die.

So you want to avoid becoming roast rider. Now your body has some ways of keeping us cool, like sweating. Yeah, it makes us stink, but better stinky than dead, after which we really, really smell. That sweat cools us by evaporation, to varying degrees. But that sweat your body is releasing has to be replaced, which means you have to take in lots of liquids… In Iraq’s 40+ C degree heat, our military REQUIRED that troops consume a liter of water an hour, and that was a “dry heat”. To a point, this cooling strategy works, especially in low humidities and temps below our bodies preferred 37 C. But add some humidity and/or temps higher than that, and the physics get real ugly fast. Quite simply, at 35 C or higher temps with high humidity your body ain’t gonna stay cool very well, especially if you’ve an older body like most of ours that could use to lose some weight and get some more exercise.

Now the weather folks have helped us in determining just how hard it’ll be to stay cool with something called the “heat index”, a summer counterpart to the infamous “wind chill”. Perusing their web pages like http://www.weather.gov you’ll find the heat index somewhere on the forecast page, and the Weather Service will often issue heat advisories and warnings based on the heat index. As a rider, you’ll find that heat indexes up to 30 C/86F degrees aren’t much of a problem. Above that, drink more liquids and take more frequent breaks out of the heat. It’s above 35 C/95 F degrees that the heat literally becomes a killer- even with every vent open on your protective gear, there’s so little difference between our body temp and outside air temp that said outside air can’t cool us much. At this point you’ll be tempted to take off the protective gear… Don’t! Above our body temp of 37 C/98.6 F degrees, that “fresh air” is heating us further, not cooling us. And above these temps, things can get fatal fast!

That’s why my personal Standard Operating Procedure is to start taking breaks at 30 c/ 86 F degrees and park it at 40 C/ 104 F- Above that it’s just too risky to ride or do much of anything. Yeah, if you’re a fit young soldier or athlete you can probably survive for months in temps hotter than that, but I and most of us haven’t been at that level of fitness for decades. Between 30 c/86 F and 40C/104 F degrees I’ll spend a greater proportion of my time off the bike and out of the heat. For example, today I’m doing about a 250 mile ride around southern MN. Got a hundred miles in during the morning before it got hot. Heat indexes are now around 35 C/95 F degrees so now I’m alternating an hour or less of riding with an hour or more in air conditioned libraries and cafes, bloggin’ away! Great way to spend a hot day… Or better yet, ride in the morning, then get home and work on the bikes in the cool shop or whatever in the afternoon.

Oh, and the BMWMOA International Rally in even hotter Sedalia, MO? No way I’m ridin’ into that tropical oven! Heat indexes are forecast for over 40 C/104 F degrees… When is BMWMOA going to learn and hold there rallies at a cooler time or place? I’m not alone, talked to a couple other riders today that are passing on the BMWMOA rally, and from the scuttlebutt on BMWMOA’s forum, a lot of riders won’t be headed that direction. Says something of the wisdom of BMW riders… Too bad the club still chooses such stupid rally sites and dates!