Sunday, January 31, 2010

Beginners Page 13 The Wind

It is appropriate that “The Wind” is number 13 of the beginners pages. I have disliked the wind from the beginning of riding. And it is always heartening to know that misery loves company. In a poll of riders, 10 times more voters said that wind is a tougher cycling challenge than hills. A Florida’s road bike maxim that I wish I could take credit for states, “For every uphill there’s a downhill, for every headwind there’s a headwind.”

When we started riding, I would check the weather or look outside and watch the tree tops sway and would say “Let’s not ride today, the wind is blowing too hard.” Christine would say “We’re in Texas, the wind always blows.” I suspected it blows elsewhere as indicated by the Florida maxim, but it really hurts when it is in my back yard. I think I did my first “official” complaining about the wind in Beginners Page # 6 “First Time Trial”. And I have continued since. But as Christine said, it always is blowing so let’s ride anyway. I wanted a good come-back so I checked the internet for various cities’ average wind speed: Amarillo-13; Lubbock-12; Abilene-11; San Angelo-10. I shut up and got on my bike and rode off into the wind.

Now riding off into the wind is not too far from wrong. Ever notice how the wind seems to blow from four different directions, each in your face? Studies have found that wind will feel like it is in your face for a 200 degree forward arc, only the remaining 160 will not feel like a direct headwind. With our winding roads, finding that 160 arc is illusive at best. Without being too melodramatic, it seems to me there is only a 10 degree arc that actually pushes me. My reasoning? As one picks up speed, there is a corresponding wind generated by the speed you are traveling; ergo, for every headwind there is a headwind. If someone finds that arbitrary 10 degree of a tailwind in the summertime, one had better go faster than the wind to generate that breeze or one finds himself in a hot vacuum.

Can’t win so ride anyway?

I read some place that a headwind slows the biker’s speed by about half of the wind speed. Now in our “average” 10 mph wind, it will slow one’s speed by 4-5 mph. When you lower MY speed by 4-5 mph, it is a significant reduction.

One of the best solutions to riding into a headwind is to draft off another biker. There are various estimates ranging from 15-30% less energy used by drafting. For example, if I am going along at 15 mph in a 10 mph wind, it takes me 183 watts (a measure of my effort) to sustain the speed. If I drop behind someone going 15 mph and expending 183 watts, by calculating a conservative 20% energy saving, I will use only 146 watts. Granted I am holding a lot of variables constant—weight of individual, weight of bike, strength, conditioning, etc., but one can get the idea that it is a lot less work to draft off of someone. (If you want to remain friends, you will take turns at lead—even if just for a short while.)

To put the above paragraph into perspective, Dr. David Wilson, in his book “Bicycling Science,” calculated that Tour de France riders generated 400 watts of power going up mountains or breaking away from the pack. This is in contrast to an average person’s riding and working as hard as possible and generating from 150-200 watts.

A caveat: the closer one is to the bicycle in front, the more wind is blocked, BUT the greater chance to rub wheels and have a nasty spill. So back off a little even though it is more work. After all, the person in front may tire and suddenly stop pedaling—disaster strikes.

Another tidbit: if you are in front and tire out, pull off to the left and let the one behind you pass while he maintains a straight line and constant speed. If there are only two of you, pull in behind the lead person. If there are several in a line, it is best to drop to last place. Each will move up a notch as the lead rotates.

A few more tips for a windy day:
---Stay indoors.
---Go fly a kite.
---Watch a cycling training film.

IF you insist on going for a ride:
---Lean into the wind. Get low. Reduce your frontal area in a headwind by moving your hands to the drop bars and keeping your elbows bent and in line with your body.

---Gears—there seems to be a disagreement among “experts.” Some say you can’t spin through the wind so put the bike in a high gear and plow through the wind. Some say to shift to a lower gear (larger cassette cog) so you can maintain a normal cadence against the wind. This group will acknowledge that you will go more slowly but rationalize that spinning is better for your knees than grinding with a slow rpm. If you are on your own; try different gear ratios and pick the one that you feel most comfortable with and keeps you moving at a speed you can accept.

---Draft off someone. This technique was covered earlier, but the front person should keep his lead time (his pull) short for maximum advantage.

---Change course. Frequently we will reverse a route so that we are facing the wind the first half of a ride and hopefully have a tailwind on the return. Our logic is that we are fresher at the start and will not be as discouraged, but many a time we have been struggling in a stiff wind and look at each other and say “We’re doing this for FUN?” And keep pedaling.

---Chant. This tidbit we still are very sarcastic about. “Experts” say to chant while riding into the wind “The wind is my friend, the wind is my friend . . . .” The wind IS NOT and probably WILL NOT EVER be my friend. But they say that like riding hills, riding in wind can make you stronger. Well, all that is better than a negative attitude of “Blankety blank wind, go to Florida!”

Note: If you want to play around with different biking speeds, wind speeds, percent grade, and required watts for the different variables—go to http://www.exploratorium.edu/cycling/aerodynamics1.html.

2 comments:

  1. Oh gosh, I agree with that poll regarding the wind - in fact, I was in that it! Seriously, it is amazing how much a head wind can wreck havoc on your trek, but when it's at your back, you can really glide along.

    Excellent article and series! Keep it up!

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  2. Yeah, I hate wind when I ride too. Makes you feel like your nose is a frozen lump.

    Thanks for the tips!

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