I first posted this back in April of 2009. A recent posting on a blog I follow reminded me of it and I figured it was a good time to republish it as a reminder and update it with stuff I've learned since then.
Here's some of things I consider, have learned, use or do when riding in hot weather.
Now, what's hot weather? Anytime, when ATGATT of course, that you're feeling hot enough to start sweating. That's my definition anyways. (All The Gear All The Time)
First off, ATGATT is not an optional thing for me. Sweating beats bleeding I've read, and I can confirm this is true through actual experience.
Vented gear is a must in hot weather, you have to let that heat your body's putting out escape somehow right? My riding jacket and pants are made of air mesh Kevlar, by Motorport, and they vent pretty good. If I choose to ride with just a t-shirt and shorts under my riding gear, it feels (while moving) like I'm just wearing the inner garments (mostly). (Sitting at a light though, you'll start to sweat, you'll be glad for that sweat, once you get moving again.)
One thing about the above concept of sweat cooling you off when you start moving....once air temperatures reach blood temperature, there's not much cooling effect at that point. At that time of day, you may want to consider finding a cool shady place to wait out the heat for a bit, if you've the time of course.
Now, for the longer rides, it's best to wear something that covers your skin so that you don't lose too much water through evaporation as you sweat. Your vented gear allows the wind to cool you through drying of the sweat you are producing, however this means faster water loss too.
I wear, a long sleeved, tight fitting, exercise shirt. It's made of a special material that wicks moisture off your body and keeps you dry; I know it seems counter-intuitive to wear long sleeves under your gear but it does work! Especially if you wet down said long sleeve shirt before you put it on wet, it's rather nice and cooling on those really hot days that we get here in Colorado.
For short rides, like commutes, I don't do this though I have been known to wet down my regular cotton t-shirt before riding home in temperatures in the high 90s with the sun beating down on me. Update: your mileage may vary but a soaked T-shirt will last you only about 30 minutes in really hot weather, then it's time to stop and soak it down again.
Get one of those neck bandannas that have water absorbing crystals in them, they swell up with water as you soak them before the ride. Wrap it around your neck, you've got major blood vessels going to/from your brain at your neck, it helps cool things down.
Get and carry a camelback-type water bag to wear on your back. I usually half-fill mine with ice and water before the longer rides, and those cooling sips I take while at stops or even while riding do make a difference! If you're doing it right, you'll run out of water in the camelback before your next gas stop, so I carry a gallon jug of water in my side case as well on the longer days of riding. Note: much cheaper to buy a gallon jug of drinking water at gas stations than the pricey "fancy" water bottles. Update: Be wary of taking in ice cold water too fast, in my case, it causes an upset stomach. Swish it about your mouth to bring up its temperature a bit before swallowing.
That same water jug is used to wet down the long sleeved shirt under my riding gear when it has become dry from the air passing through your vented gear.
When you go to the bathroom, if your piss comes out a deep yellow, you're not drinking enough. You should really have to go often if you're hydrating correctly. Dehydration is not something you can tough out, it will kill you if you try to gut it out. Headaches are an early sign, if you stop sweating in the heat, heat stroke is not far behind. Drink water, often!
Drink water, not beer or coffee, alcoholic drinks and caffeine are diuretics....meaning that they make you pee and thereby lose more water. I don't drink beer at all if I am riding so that's not an issue though I confess being addicted to my morning cups of coffee. Sodas don't count, water!
I've read somewhere where folks pour water into their helmets to soak into their helmet liner material. I've not tried it but it seems to make sense, just make sure you dry out your helmet at the end of the day, no sense getting mildew and such growing in your helmet!
Keep your skin covered, exposed skin will sunburn and lead to your sweat evaporating that much faster, causing faster water loss. Don't forget the back of your neck when applying suntan lotion.
Hot weather usually means lots of sun exposure, get some good sunglasses or a darkened visor for your helmet. It helps prevent headaches from your eyes being in the permanent squinting mode due to the brightness of your surroundings.
If your ride an air-cooled motorcycle, beware of your engine temperatures getting too high in prolonged stop and go traffic. Even oil-cooled motorcycles will overheat, especially the ones with fairings that tend to trap air in slow moving traffic. Brigitta, my 1987 R80 is air-cooled and gets pretty hot in heavy traffic. Maria, my 2004 R1150RT, though oil-cooled did once in a while get pretty close to overheating as well. Be prepared to pull over and let things cool down if you have to. The jury is still out on my newest ride, the Suzuki V-Strom with it's large radiator and secondary oil cooler setup.
Hot weather on asphalt, causes said asphalt to become soft. If your motorcycle's parking spot is black asphalt or similar, make sure you've a wide footprint side stand base or you'll find your motorcycle on its side when the side stand digs into the asphalt in the heat and your poor motorcycle topples over! I carry a small plastic disk, about three inches in diameter, that I place under the base of the side stand. Worse comes to worse, find an old soda can, crush it down vertically and use that!
I carry a motorcycle cover which folds up pretty compactly on the days when I have to leave my motorcycle out in the hot sun. It's large enough to cover the gas tank and most importantly, that black leather seat for when I return to the motorcycle, no sense sitting on a hot seat!
Carry drops for your eyes, they're going to dry out, especially in the drier climes.
That's all that comes to mind for now, please leave a comment if you've tips I've not mentioned.
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