How hard was the wind blowing?

[marni]

I did a short ride today. Actually I intended to do a long ride since the weather report said winds 5-8 and with temps in the mid 60's- a thaw for us. After struggling through 20 miles of headwinds that were definitely more than 5-8, at a pace of 10 mph which I was struggling to maintain, I found a side road and coasted for 2 miles at 16 mph without peddling before I gave up and tunred across the wind to head home. If you live in the Texas plains, you don't need hills cause you just have to fight the wind. Of course then you never get the joy of a downhill, and rarely the ease of a tailwind. Time to take a day or two off I guess.

[salsabike]

Marni, a long time ago I posted a formula that my engineer husband Chris gave me that explains why you suffer more from a headwind than you benefit from turning around and using it as a tailwind. It was a comforting and amusing way to quantify headwind suffering. I will try to dig it up for you. And 20 miles of headwinds IS a long ride. :)

Chris actually came out to Texas last May and did this ride: https://sites.google.com/site/texasstampede1200/. And, he said, out of the three and a half days, about three were headwind days. I believe I remember hearing the phrase "soul-sucking headwinds". But he had a great time and really likes the Texas randos.

Put your feet up and know you had a hard-workin' day. :)

[luvmyguys]

Marni - we were fighting those same winds today.

Salsa - could you point me to that little formula??

[salsabike]

I promise I'll post it on this thread when I unearth it.

[thekarens]

Another one who didn't appreciate the headwinds today. I was sticking with an out of towner from Austin. I think we were both thinking it would be an easy ride for her since it's flat here, instead the headwinds were beating us up.

[TigerMom]

You are right. Head winds are as difficult or more difficult than hills, especially since winds can suddenly start/stop and blow you at different angles.

[kernowcyclist]

Oh boy, tell me about head winds! We live in a windy area and it's very 'up-and-down' too so more often than not you're faced with a ride that hits you with uphill headwinds at some point. It's ...errrr... character-building! But recently, with the terrible rain and storm force gales (90mph!) the UK has been suffering it's been impossible to get out on the bikes, too darn dangerous for one.

Anyway... today gifted us a brief respite, sun, blue sky and only a light wind. So hubby and I grabbed our bikes and set out to cycle to the nearest lake, a round trip of only about 10 miles (mostly uphill coming back!) with a large hot chocolate drink at the cafe by the lake, it was heaven just to be out again!

[rebeccaC]

If I’m in a hurry to get somewhere I’m not using my bike.:)

I look at headwinds as helping improve my fitness! Getting aero, gearing down to find a fluid spin and keeping my mind on positives usually makes for a good ride. Strongest headwinds I've had were on Ragbrai. I was down to single digit speeds and enjoying the challenge….and looking for someone big to draft behind every now and then :)

[salsabike]

Okay, here it is as Chris explained it to me. Fluid drag force (air is a fluid—it takes the shape of its container) is proportional to velocity squared. Factors include the density of the fluid (so air is not as dense as water, for example); the drag coefficient of the object (bike, your clothing, etc.), the projected area in direction of motion (that’s why you get aero, to decrease your area), and velocity.

The drag force increases as the square of the wind velocity relative to the bike. Downwind, you subtract your speed from the wind speed. Upwind, you add your speed to the wind speed. So, for example, you have a 15 mph wind and your bike is going 10 mph. Downwind, the push you get is proportional to (15-10) squared = 25. Upwind, the resistance is proportional to (15+10) squared = 625. Fun, eh? Thanks to my cool engineer spouse for the explanation.

[marni]

that is the most lucid and useable explanation I have heard. Thank you to your and your husband.

[Melalvai]

The drag force increases as the square of the wind velocity relative to the bike. Downwind, you subtract your speed from the wind speed. Upwind, you add your speed to the wind speed. So, for example, you have a 15 mph wind and your bike is going 10 mph. Downwind, the push you get is proportional to (15-10) squared = 25. Upwind, the resistance is proportional to (15+10) squared = 625.
That is so cool to have an actual science type explanation and a formula of what I have known for a long time. Thank you.

I have more than once gotten myself in trouble because I was going into a wind and working harder than I realized.

[salsabike]

I know! It's oddly gratifying to grasp the magnitude of all that work we're doing when we plow into a stiff headwind.

[marni]

today was a warm 80 degrees and windy two shots of pickle juice ride. I was averaging 14 mph and the wind was 20 mph which means that the proportional resistance force was 1600. I did 50 miles mostly with headwinds today and 45 miles yesterday. No wonder my legs my legs are really tired .