Thursday, August 12, 2010

It's Frigging Science: Too Hot? Ride Faster.

With a similar sweaty eye stinging heat wave sweeping the nation, almost four years ago to the day, I wrote a post about cycling wind chill and discovered that you can feel a teeshy tish cooler, if you ride faster.  Against all the recommendations from meteorologists and health departments, with a heat index of nearly full-on Africa hot, I went out for a ride.  For the record I did not die.  In fact, I felt cooler.  Not a whole lot, but on a scale of Sudan to South Africa, I felt Southern Congo.  Here's a revisit of that "It's so hot my hands are slipping off the bars" post.

Four years ago when zippin’ down Kellogg Ave (now Riverside), a slightly downhill road along the Ohio River in Cincinnati, at 27mph, I couldn’t help but notice I felt cooler than when I was climbing a hill at 10mph into Eden Park.  Does wind chill apply in warm weather too?

These are the thoughts that go through your head when riding by yourself.  If my memory would serve me better on bike rides, I'd have retired like a Jet Blue flight attendant a long time ago having acted on one of my brilliant bike ride induced million dollar ideas.  These thoughts are precisely what makes cycling such a great escape…and precisely why your co-workers think you’re a kook for wearing spandex.

So, when I got back from my ride, I did a little Internet research on this phenom-enom-enom-enah.  Some weather websites said their wind chill factor calculator couldn’t be used if it was over 40 or 50 degrees.  Huh?  But, I felt cooler flying on my bike in 90-degree weather at 27mph.  The dog doesn't stick his head out the window to catch bugs.  Surely there must be a wind chill effect while cycling…a cycling wind chill. 

So, I dug a little deeper, expanded my search, and wah freakin’ lah, I found a Wind Chill Calculator that did accept temperatures over 50 degrees.  (insert evil laugh here)  Here’s the link:


So, I started plugging in numbers.  And, for the most part, it seemed to work.  That is, until I plugged in 100 degrees.  Over 100 the calculations came back saying it would feel even hotter riding at 10-30 mph.  No way Al Roker. 

But, maybe not.  Maybe there’s a temperature where no matter how fast you're riding, your body just can’t dissipate the heat any faster and thus the wind chill effect wouldn’t be in effect.  Yo!  The cycling wind chill is not in effect.

Here are the results of the numbers I plugged in.

Temp Bike Speed Cycling Wind Chill
100      30                         104
100      20                         102
100      10                         100

90        30                          87
90        20                          87
90        10                          89

80        30                          73
80        20                          75
80        10                          77

It seems like to enjoy a noticeable cycling wind chill, the speed needs to be over 20mph and the heat preferably south of 90 degrees.  However, there are other ways to feel cool on a ride, like using white bar tape, having only one gear and keeping your sunglasses on the outside of your helmet straps.  If you can't do that, think of the other things that can impact on how cool you feel when you ride like: wearing a black plastic trash bag instead of white lycra or a shaded bike path along a river, as opposed to climbing with a 50 pound huffy up exposed blacktop.  Experience has proven to me on a mountain bike it feels hotter wearing a sasquatch outfit when riding in a field of tall grass as compared to riding naked in a shaded forest. 

So there.

1 comment:

Mr Fixie said...

Hah! The point of diminishing returns comes up fast when riding a 35 pound comuter rig with loaded panniers!

At 18mph on the flat I'm working my a$$ off, and getting 2°F credit on a 90°F day. But I'm still loving it, cuz we live with no AC in our house! In fact it's broken at the office too, and everyone is whining, except me! I'm looking forward to the ride home, and that two degree credit!