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14

Take it easy and shift to an easier gear. It sounds like your main problem is not the reduced speed but exhaustion. The good thing with headwinds (unlike hills) is that most bikes have low enough gears available to make pedaling against it easy. Aerodynamics is mostly affected by frontal area and shape. Close fitting clothes (and backpack), low and narrow ...


13

If the effect of wind resistance was linear with respect to speed, then yes, the forces would balance out. That is to say: if pedaling into a 20 mph wind was only twice as hard as pedaling into a 10 mph wind, the forces would balance. But this is not the case, as @Daniel mentions. The effort to overcome the 20mph wind is more than twice that needed for the ...


12

The most accurate way to do it would be with a pitot tube to measure wind velocity and then to contrast that against speed-over-ground from your GPS or wheel speed sensors. Before one laughs about the science-fiction nature of this, there's a product that does so: The PowerPod (link is to DC RainMaker's review of it). The Isaac software that comes with the ...


11

You can do it, because your bike is connected to the ground. The work done when moving an object is proportional to distance and resistance force (which consists of air resistance and rolling resistance for bikes). The air resistance depends on air speed (ground speed + wind speed), but distance depends only on ground speed. Going slower reduces the energy ...


11

When your biggest problem is a headwind, being more aerodynamic helps. In a severe headwind, it becomes more important than many other considerations. I posted a link in the comments to GCN's commuting aero challenge. This shows that panniers are bad into the wind, backpacks much better, and a bikepacking saddlebag better still. Yes they went fast, 40 km/...


10

As you might expect, the exact down slope you would need for a full answer will depend on how much drag you and your bicycle produce. If you are very aerodynamically efficient and there are few losses through the bearings and tires, the slope can be shallower. If you create a lot of drag either via aerodynamic inefficiency or mechanical and rolling ...


10

One thing to understand is that wind resistance is roughly a function of relative wind speed squared. That is, if your speed, relative to the wind, increases from 10mph to 15mph, the "drag" from wind resistance doesn't simply increase by 50%, it increases by about 120%. So your effort level, due to wind resistance, will more than double. (On the ...


9

Anything colder than -55F (-48C) is difficult to mechanically maintain. Most lubrication products on the market for cold weather are rated to -60F (-51C). Which means that at -50F (-45C) they become almost unrideable and at -55F (-48C) pretty much unrideable. I am aware of products rated for colder than that, but they have issues that when stored at room ...


8

You can do this because of the gearing of the bike. When you're riding at a slower ground speed, if you shift to a lower gear to keep your pedal RPM the same, then the same force on the pedals produces a higher thrust at the tire. Even if you do not shift, it is easier to produce higher force on the pedals at lower RPM. The strength of a cyclist is ...


8

The Varna, which was one of the best bikes in 2003 has speed + power graphs up from their Battle Mountain runs that year. At 80kph Sam was putting out about 225 watts, but accellerating. There's also a 0.5° slope to consider. This article suggests that the bike uses about 150W at 50mph/80kph. Sam weighs about 80kg, the bike about 25kg. Let's call it 110kg ...


8

Having ridden near Bristol this morning in a similar forecast gust speed, I'd say you're right to be worried, but keeping aware of the wind direction and speed can make a huge difference. For example: passing side roads on your left, if the wind is coming from the left, you may want to aim slightly towards them so that you get blown back towards the middle ...


8

When you're in font of the rider that you want to help, then the more aero you are, the less shelter you give. Riding in a low body position, head tucked and arms narrow makes it easier to ride at speed, but means that you aren't puching through the wind as much for the rider behind you. You'll want to sit as upright as possible, arms a little flared ...


7

We like tailwinds as the effort to ride at a given speed is lowered. In the same token we like slight downward slopes. If you base your riding on effort, rather than a fixed speed, you will automatically utilise a slight tailwind. If you however ride at a fixed speed, you simply had an effortless ride. In other words, you missed nothing.


7

A tailwind reduces your relative airspeed and therefor the drag you generate. You can go faster relative to the ground with the same power output. The only time increasing your profile might be beneficial is if the wind is traveling faster than you are, relative to the ground .... Unless you cycle slowly or the wind is very fast, it's usually not the case. ...


7

Yes absolutely. The depth of a rim is directly related to the side-area, and a gust of wind will have more of an effect on a larger surface. The largest wheel surface area is a solid disk, and even pros will prefer an open wheel to a disk wheel on a race day with a gusty wind forecast. If there are a lot of sidewinds anticipated, an old-school box-section ...


6

@Daniel has made several comments that capture what experienced cyclists have learned. You think something like I'm going well, or killing it, or even (as happened today) this looks like it's uphill, while blasting along. When you stop you discover the awful truth. It's a headwind home. The reality is that we nearly always have a headwind, especially as ...


5

The stock advice is to put zero reliance on your ears ever. There's this issue, there's the related issue of wind direction keeping you from hearing a car even not at high speeds, and there are extremely quiet cars. Basically the choice is look back a lot and get good at it or use a mirror.


5

If you are biking along and you encounter a terrible smell -- look around and realize that it's you yourself that you're smelling -- then you're in a tailwind -- and that it's time you washed your bike jersey. Thank you for the downvotes, I'll show myself the door. :-)


5

Specific product recommendations are off topic on this site as they tend to become obsolete quickly. There are plenty of breathable windproof, cycling specific jackets available and reviews are easy to look up. Wearing a wind-permeable fleece on a bicycle in cold weather is less than optimum because cycling always involves wind (although you are moving ...


5

The answer to your questions is not straighforward, as shown below. The easiest to answer is your first question: are X and Y the same? No, they are not. This follows from the formula for the air-drag power Pa = ½.rho.Cd.V.(V-Vw)² , where rho is air density, Cd is drag coefficient, A is frontal area, V is forward speed, Vw is wind speed. Suppose that for a ...


5

Apart from improving efficiency (well covered in other answers), which quickly gets into marginal gains without spending big money, it helps to also tackle this from a phycological point of view - Think about time, not distance. "Today is going to be a 30minute ride, yesterday was a 45 minute ride". A head wind means more work, but if you give ...


4

Some things to try to make your bike less susceptible to wind gusts. Maintenance - check your headset is not loose and has no discernible play. Ensure your bike frame is true so that the front wheel leads the back wheel precisely and that the fork is not bent at all. Check your wheels are true and that your wheel bearings are smooth with no wobble. All ...


4

There are more factors: bike speed bike style / tire size rider skill I ran the math If you are going 10 kph, get pushed off 20 degrees, and it takes 1 second to correct (point into the wind) then that is 0.95 meters If you are going 20 kph, get pushed off 20 degrees, and it takes 1 second to correct (point into the wind) then that is 1.90 meters If ...


4

@Superdesk has the right answer, but I thought I'd add some math to give an impression of the size of the difference. As others have stated, drag is a quadratic function of relative wind speed. This is why you need a lot more effort to go from 0 to 10 km/h than from 20 to 30 km/h on a bike. Suppose that you like to bike at 20km/h. If you go for a ride on a ...


4

Ok, let's start with wind chill. The faster the wind, the more chill Wind Chill chart from the National Weather Service Read along the top for the temperature without wind, then down for wind chill at different speeds. So, for example, at 15 degrees Fahrenheit (-9°C) in a 15mph (6.7 m/s) wind, effective temperature is 0 degrees Fahrenheit (-18°C). (chilly!)...


4

For constant input pedaling power, a sidewind will slow a cyclist down. The sidewind exerts a force on the cyclist, so they have to steer into the direction of the wind to keep on their intended course. The action of the tires against the road producing a counter force also creates a force opposite to the direction of travel. Unfortunately headwinds have ...


3

Partly it's due to the way that wind speed is measured. The standard for wind speed is to measure it 10 metres above ground level. Closer to the ground, an effect called the boundary effect kicks in and the wind speed is slower (in fact, the wind speed on the ground is effectively zero). According to this site, wind speed on a flat grassy plain can be ...


3

I'll start by saying that finding solid data on wheel aerodynamics is tricky at best. Some of the better sources are worth taking the time to read in full, and provide much more information than I can provide here. For example, see the article from Tour Magazine [1] that covered the Mavic Cosmic Carbone SLR (similar, but not the same as what you asked ...


3

I think it will help the most to simply having a better understanding of wind chill. A wind chill of 1 is a wind chill of 1, regardless of the air temperature you start with ( Granted, to make matters more complex, there's not really a standard for calculating wind chill ). The wind chill you experience personally while on your bicycle depends entirely on ...


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