How many MPH do you drop when going against headwind???

[FreshNewbie]

Today I rode in a 18-19mph headwind half of my morning ride. Usually i can hold 18-20mph on a flat but as soon as i face that wind my speed drops to 14-15mph without shifting. I am not fast as it is and to drop speed like that is very dissapointing. Am I out of shape? or it sounds normal? Have nobody to compare to...... Any ideas?

FN

[SnappyPix]

FreshNewbie,

Sounds perfectly normal to me - and if you can maintain 18-19mph on the flat, it doesn't sound like you're out of shape to me!
Typically I can be motoring along at anything from 30-40kph on a nice stretch - but give me a big gusty headwind and this can drop to anything between 20-30kph, depending on the wind speed (sorry, converted to metric when arrived Down Under!).

Headwinds can be pretty demoralising and can totally break a ride - sometimes it's like hitting a wall, cycling through treacle, or at the very worst - pedalling backwards (almost did that once in "Windy Wellington"!!).
Typically I'll try and drop a gear or two, so I'm spinning at a higher cadence - headwinds can be a bit like hills, don't want to mash them!

[salsabike]

The force that acts against you riding into the wind is proportional to the square of the relative wind velocity. If you are going into a 10 mph wind at 10 mph, the force is K*(10+10)^2 = 400 * K. If you are going 20 mph into a 10 mph wind, the force is K * (10+20) ^ 2 = 900 * K

The multiplier K depends on your frontal area and how aerodynamic you and your bike are, and the viscosity of the fluid you are moving through. It's harder to bike through water.

[mimitabby]

hey Salsabike i love your physics

I have been blown by side gusts that almost knocked me down. (scary!)
Wind is terrifically strong and if it slows you down, you're just obeying the laws of physics. Even Lance can't go as fast into a headwind as he can without!!

[SnappyPix]

The force that acts against you riding into the wind is proportional to the square of the relative wind velocity. If you are going into a 10 mph wind at 10 mph, the force is K*(10+10)^2 = 400 * K. If you are going 20 mph into a 10 mph wind, the force is K * (10+20) ^ 2 = 900 * K

The multiplier K depends on your frontal area and how aerodynamic you and your bike are, and the viscosity of the fluid you are moving through. It's harder to bike through water.

I THOUGHT it must be something like that!!!

All you need to know is that the wind is never with you, it's either against you, no wind at all, or you're just having a really good day!
And even if it's against you, stone me if it doesn't change direction, so it's there again on your way back!

[mimitabby]

And even if it's against you, stone me if it doesn't change direction, so it's there again on your way back!

i thought that was a Seattle weather condition. It happens in New Zealand too?

[Lifesgreat]

Wind is terrifically strong and if it slows you down, you're just obeying the laws of physics.

I guess I ought to obey SOME laws out there. Oh, I will obey the law of gravity too.

[salsabike]

Yeah, headwinds both ways. That always amazes me. I'm always sure I'll get an equivalent tailwind as a reward for bucking the headwind on the way out, and it just doesn't work like that. But no matter how much I know that, I'm always a little disappointed. On the few occasions when it does happen, though---how much fun is THAT??? Screaming back home at 20+ mph. Love it.

[betagirl]

That happened to me on the 300K. I was all stoked about having a tailwind back. Not.

For the original question, I'm about the same as you with speed. 18-22 on a flat. When I'm going into say a 10mph wind, I drop to around 17. If it's stronger, say 15-20mph, I drop to like 15. So if that's being out of shape, I'm right there with you I do try to get down into the drops when the wind is blowing. I gain a mph or 2 if I do that.

[FreshNewbie]

Thanks for the replies, i guess i am not alone. I thought maybe I am not strong enough. Also, forgot to mention that I have to pull 35lb steel bike so I guess that will make it even worse! would be interesting to see what happens when i will buy myself lighter bike, can't wait.

FN

[ladyjai]

i was out riding this last saturday 3/4 of the way with headwinds, and a fixed gear bike. at one point we finally saw no wind. it was great, our speeds moved up to a comfortable 20, then like a wall, we were hit with the wind all at once. it was like brakes were applied to the bikes, and we dropped 3mph in an instant.

[Geonz]

I've decided that most people who hate wind mainly have trouble dealing with that number on their computer getting smaller, and if they'd get over it, they could have fun in the wind, too. It's better workout per mile, after all! In general, going out too hard at first makes for less fun, and if you're trying to keep the numbers up in the face of a headwind, you're going to do that. I don't mess with the numbers, and just let my body work as hard as it was going to work.
Winds here will take my 17 mph down to 11 or 12 ... sometimes 6 or 7 but then I figure it might pick up a cow and hit me with it...

[DeniseGoldberg]

I'm not fond of headwinds either, but sometimes it's the sidewinds that really scare me.

I was on the Big Island of Hawaii, luckily riding on a very lightly traveled road, when I was hit by a blast of wind that moved me from my usual position on the right side of the road all of the way across to the edge of the pavement on the left side of the road. (And at that point I was already leaning into the wind to stay upright!) I'd like to think I would have had the presence of mind (and the ability) to lay the bike down if there had been traffic - but to be honest it felt like I was totally out of control!

And I remember a headwind day on my tour of Prince Edward Island last year where I was pedaling down a hill in my granny gear. Ouch.

I'm not a fast rider anyhow, and I've learned to not get upset when a headwind slows me down. After all, it's part of riding, and I like riding!

--- Denise

[caligurl]

FreshNewbie,

Sounds perfectly normal to me - and if you can maintain 18-19mph on the flat, it doesn't sound like you're out of shape to me!

i second that! 18-19mph in a headwind.... you have NOTHING to worry about!

[maillotpois]

I don't drop nearly as much mph as I do when the road goes up.