New to myWindsock are Virtual Athlete Rules. They are, to a programmer, what we call conditional operators. Conditional operators are fundamental constructs in programming that allow you to make decisions and control the flow of your code based on certain conditions. They enable your program to execute different sets of instructions depending on whether specific conditions are met or not. The most common conditional operators are if, elif (short for “else if”), and else. These operators are primarily used in languages like Python, C, C++, Java, and many others.
In myWindsock – they work broadly the same as in high level programming languages. For example, we might want to see what would happen to our overall time if we drop our power to a given number over certain speeds, sit up during certain portions of the course or raise our power over certain gradients.
Setting Rules on myWindsock
Firstly, add a course or segment to your planner. I’ve added a triathlon that I’m racing in October in Ibiza – pacing is vital in triathlon so playing with a pacing change on a triathlon course seemed smart.
We start with a perfectly evenly paced 300W for the bike course. This gives us a time of bang on 2:15 for the bike.
How to set rules…
Open the forecast on myWindsock.com
Scroll to settings and click the orange “Change Settings” tab
Here is where you will find performance rules…
Let’s add some rules and see what happens…
I’ve added speed related rules – the aim is to simply whack climbs and coast fast descents…
This has taken almost two minutes off our bike split for less power and essentially the same normalised power (I certainly can’t really tell a 1% change in NP). We can see here where the rule change has allowed us to use less energy.
Let’s take it a little further and shrug extra hard on the flat sections and let’s say, for argument’s sake that this reduces our frontal area by 5% and this has a 1:1 mapping with cda (which may or may not be true – seems like the sort of thing you might want to test). The other thing we will do is really whack the steeper sections and hit 400W when the road tilts over 9.9%. The assumption of the rules is when none of the conditions are met we ride at a steady 400W.
This has shaved another 23s off our total moving time and reduced our average power by a single watt.
Let’s further adjust the pacing strategy by simply setting the uphill power to 330W and the downhill power to 200W – which will be the default settings until our pacing rules that we’ve set kick in as conditions are met. We will also alter the cda values to a slight increase when climbing and decrease when descending…
We’ve managed to further drop our time by another two minutes with a lower average and normalised power by descending slightly slower and climbing slightly harder.
We can see here that, as well as pacing a long effort evenly, riding the road is also important. Riding harder on the climbs and gentler on descents will mean you get from A to B both faster and having used less energy. At the end of our little experiment our moving time is over 4 minutes faster than the perfectly evenly split effort for less watts.
If you want to take your pacing and race planning to the next level, join athletes who have won Olympic medals and World Championships by signing up to myWindsock here.
Cycling CdA, also known as Aerodynamic Drag Coefficient (CdA) in the context of cycling, is a crucial concept in the study of aerodynamics that plays a significant role in determining a cyclist’s performance and speed. CdA is a measure of the resistance a cyclist experiences due to air while riding, and it directly affects the energy required to maintain a certain speed.
The CdA value represents the aerodynamic efficiency of a cyclist and their equipment. A lower CdA indicates a more aerodynamic posture and equipment, resulting in reduced air resistance and improved cycling performance. On the other hand, a higher CdA signifies higher air resistance, leading to a decrease in speed and increased energy expenditure.
The CdA equation involves a complex combination of various factors, including the cyclist’s body position, the shape of the bike frame, wheels, and even clothing. Each of these factors contributes to the overall aerodynamic drag that the cyclist experiences while cycling. To determine a cyclist’s specific CdA value, researchers and cyclists often perform CdA tests in controlled environments, such as wind tunnels or virtual simulations.
To simplify the process of calculating CdA, cycling enthusiasts and professionals use myWindsock’s CdA calculator to estimate the aerodynamic drag coefficient based on a ride FIT, TCX or Strava Activity data. As this is myWindsock, environmental factors like wind speed and direction, and air density are included in the calculation.
myWindsock simplifies CdA analysis for every activity
MyWindsock combines weather dynamics and ride data to produce a CdA value for cyclists. By considering real-time weather conditions like wind speed and direction, along with data collected during a ride, such as speed, power output, and elevation, myWindsock can estimate the CdA value more accurately.
Road bike CdA optimization has become a crucial aspect of professional cycling, as even small improvements in aerodynamics can lead to significant advantages in competitive races. Cyclists, coaches, and engineers work together to find the most aerodynamic positions and equipment setups to maximize performance and reduce energy expenditure during races.
In summary, CdA in cycling refers to the Aerodynamic Drag Coefficient, a measure of the resistance a cyclist encounters due to air while riding. It determines how efficiently a cyclist can move through the air, and lower CdA values are sought after to enhance performance. The myWindsock CdA calculator incorporates weather dynamics and ride data, helping cyclists optimize their riding positions and equipment to minimize drag and improve their overall cycling performance. By continually refining their CdA, cyclists can gain a competitive edge and achieve better results in their races.
The UCI Gran Fondo World Championships provide an opportunity for amateur cyclists to compete at a global level and earn the title of world champion in their respective age categories.
The time trial event consists of multiple age categories for both men and women. The participants typically qualify for the UCI Gran Fondo World Championships through national or regional qualifying events, which take place in various countries.
This year’s Championship is East of Dundee in Scotland.
To begin our analysis, we’ll set up our Virtual Athlete as a fairly competitive male age group rider.
The Course
A 22.7km simple out and back course makes this a straightforward fight of power and aerodynamics between the riders. For riders at mid day the current forecast is a Westerley wind averaging 10mph gusting to 20mph. In some ways this simplifies things further for the riders, tailwind out, headwind back. For the British riders, who are used to their local cycling club time trials and the British weather, there will be a very familiar feel to the event. However, the question that will be high on the riders minds right now is “how do I extract speed from this course for that wind direction?”.
Firstly, is it hilly?
No. Our resistance analysis shows for our virtual rider the most significant force acting against the rider is Air Resistance. That said, in the final 2 minutes of the ride the slope brings our virtual rider down to 30kph, from averaging 47kph this will no doubt feel torturous.
For couple of occasions on the return the speeds will drop.
Let’s look at the wind
Blue indicates the outbound tailwind. Red is the return leg, into the wind.A slower return into the wind increases the time spent battling the headwind.
Okay, but how will the ride feel?
This is where will pull out the myWindsock Feels Like Elevation chart. We’ve combined the wind with the elevation profile to give you an ‘on the bike’ feel when all resistances are considered. Here is what the Feels Like profile looks like. In light grey is the elevation, the coloured profile is the Feels Like Elevation profile. The tailwind start gives a significantly easier feel to the road than the traditional profile suggests.
Using a typical time trial positions of 0.200 CdA and 340 Watts, your own setup my give a different graph.
Pacing
Now we turn to that crucial question for the competitors, “how do I pace it?”. To do this let’s use some myWindsock rules.
Performance rules enable you to experiment with various cycling scenarios.
Firstly an evenly paced ride at 340 Watts.
Next, more power during tailwind
Our virtual rider is averaging 340 Watts. Let’s add a rule to push an extra 5 Watts during the tailwind and 5 Watts less for the Headwind. A difference of 10 Watts. The result…
No difference. (We did have to double check that)
Next, more power during the headwind
So this time we flip the scenario and put out the extra 10 Watts during the headwind. Let’s see what this does to our virtual rider’s time.
A small advantage of 3 seconds. So if in doubt an evenly paced ride with a slight bias to the return leg would be our recommendation.
Increasing power on the slopes
Next we look at the advantages of adding more power during the slopes. In our analysis there are two locations you want to be strong. Both occur on the return leg.
We increased our Virtual riders power by 5 Watts. The Delta Variance chart shows in green where these 5 Watts return the greatest reduction in time. On the return leg, there is more green. Thiw was anticipated by our previous experiment which increased our power on the return into the headwind and gave us a 3 second advantage for the same overall power.
However we now see where the gains are (in green). Our advice, be strong at 14km and in the final 2km give it everything.
Delta Variance. Time is saved at the greatest rate where green.
In Summary
To finish off our analysis, we turn to the rolling average speed graph. This gives us a picture of how our average speed will evolve during the time trial. This way we know what to anticipate speed wise.
The Rolling Average Speed graph shows the evolution of your average speed during your ride
A rapidly increasing average speed peaking at the turn. The return into the headwind sees the average speed drop by around 2kph by the finish.
So overall our recommendation is to ‘bide your time’ on the out leg and ensure there is something left for the final couple of km. If you are competing on Monday, view the current forecast and have a fantastic ride!
Recently I was out for a ride with a couple of people and we were discussing how best to pace a rolling bike course. The questions that came up were the following…
Is it faster to ride a smooth power or ride climbs harder?
If it’s faster to punch up climbs, how hard should I do this?
If it’s faster to ride climbs harder, why is this the case?
The plan here is to take a look at some physics, then use myWindsock to answer the questions that we’ve asked…
Aerodynamics and speed
As you ride a bicycle, you experience resistance from the air that opposes your forward motion. This resistance is called aerodynamic drag. When you move slowly, the drag is relatively low, and it doesn’t significantly impede your progress. However, as you go faster, the resistance from the air becomes more pronounced, and the aerodynamic drag increases.
Imagine sticking your hand out of the window while driving a car. At lower speeds, you’ll barely feel any resistance, but as you increase the speed, you’ll notice that your hand encounters more and more force from the air.
This relationship between aerodynamic drag and speed is not linear but rather exponential or quadratic. It means that when you double your speed, the aerodynamic drag doesn’t just double; it increases significantly more. This non-linear relationship is why it becomes much harder to maintain high speeds, especially on a bicycle, as you need to work against the increasing resistance from the air.
The non-linearity is what’s important here. It tells us that not all input power is created equally. Remembering that power is the ‘time derivative’ of energy – ie given a total energy budget, the power is the speed of energy expenditure. High powers deplete your energy reserves faster and low powers deplete them slower. Riding at 300W for 5 minutes is the same amount of mechanical work as riding at 600W for 2.5 minutes (of course, it probably uses less energy as humans tend to be less efficient at 600W).
So we have two concepts here – an energy budget for a given course and the idea that when you go twice as fast, the resistive forces increase 4 times as much. This should lead us to conclude that by going harder when the bike is moving slower, you spend less energy on your surroundings. The increase in speed for a given increase in power is greatest when speed is lowest.
We have our first answer then, it’s faster to ride the climbs harder as opposed to riding a smooth power.
How hard should I go?
This is the age-old pacing question. If you cook yourself on every single climb – you’ll likely run out of gas at some point during your race so you probably don’t want to do that, you don’t need a physics engine to tell you that riding every 5 minute climb in a 25 mile TT as hard as you can is not smart – the second climb will feel very hard. That said, go too gently on the climbs and you’re wasting watts in the wind on the descent. I think it’s time to run a myWindsock simulation and have a chat about power-duration curves…
A power duration curve from 2023 for an average time trialist (me).
This is my 2023 power duration curve and it tells me my best efforts for this year, this is how I would judge the power that is sustainable on climbs. For example, imagine a 25 mile TT with 4 climbs that total 5 minutes in length along the course. The way I would do it, is check my duration curve and add up the lengths of the climbs. So in this race, the duration of climbs is 20 minutes (4 x 5 minutes) – thus I would pace the climbs at this power. There’s no science behind this method, but personally I find that this allows me to recover quickly enough on the descent to begin pushing on the flats.
Let’s go into how myWindsock can tell us which is faster…
Simulation time…
The windsock map of our chosen segment, a climb then straight into a descent.
For this example I found a segment called “climb and descent” in France. Which, on the day of writing, happens to have a stonking tailwind.
Run 1: Even Split Pacing
We can see a very low wImpact but notice the time, 14 minutes and 15 seconds and the weighted power and the average power are the same. Now let’s try an extreme power split and see if we change the time.
An insane pacing strategy – whack the climb and freewheel the descents
This pacing strategy is much the same but with a lower average power and a higher weighted power. This lower average power means the same time (roughly) is achieved with a lower overall energy expenditure. That said, you need to train to achieve robustness to these higher average powers.
A more sensible pacing plan…
This effort is almost a minute faster than the smoothly paced effort despite being physiologically almost the same. This suggests that there’s an optimal measure of whacking the climb and peddling on the descent in terms of a pacing strategy.
Using myWindsock to set some rules
We have set a rule such that if the speed of the virtual athlete is greater than 60kph, the power that athlete rides at goes to zero. We notice a loss of 13s here but the power reduction is huge. This kind of selective pacing is something that may interest triathletes in particular as the aim is to get off the bike with as low an average power (thus less energy expended) as possible to be in the position you want to be on the run.
These personal rules are quite easy, can be programmed into a pacing file or just remembered. If I am going at some given speed, ride at some given power. Using myWindsock rules is an excellent, simple, means of setting a pacing strategy for a rolling course. By calculating your cda you can work out roughly how many watts you lose to air resistance at a given speed and once this is over a given number – which will depend on duration of the race – you should stop and freewheel.
myWindsock has a host of features to help you nail your next race – sign up here.
We get a lot of professional triathletes in our Instagram DMs asking various questions and getting us to do various simulations. One thing that’s of great concern to this group is the impact of drafting in a race. In Ironman branded racing, athletes must ride 12m apart (though it’s observed to sometimes be slightly closer than this on occasion). Sometimes there’s a 20m draft rule but this is often enforced inconsistently so for the purpose of today we will focus on the difference that can be made by drafting at 12m.
Without spending days doing a bunch of computations – we can have a look at some off the cuff experiments done by various internet nerds and input the numbers they received into a route in myWindsock to have a look at time savings based on what a pro might do.
Our virtual pro
In order to run the numbers, we will simulate a virtual pro. Let’s call him Andy, as I know an Andy that likes to spend a long time off the front of professional Ironman races alone so the name seems to fit. Let’s imagine his system weight (75kg athlete plus 10kg tri bike) is around 85kg, his cda is around 0.25 (he’s not been in the wind tunnel much but is fairly aero) and he rides an Ironman at 300W. If we head to Kona and simulate this course we can ask ourselves two questions…
How fast does Andy go?
How much energy does he use to go this speed?
Ironman bike splits have two competing priorities, get off the bike as fast as possible but having used as little energy as possible (remember, you still have to run a marathon after this). Let’s head into myWindsock…
Here’s our virtual pro’s bike split when they’re riding alone. A decent ride…
Ok, so Andy’s doing a decent Ironman bike split here but, let’s say for the sake of argument he swims a bit slower and has a mate to ride with. How does the calculation change?
What is the impact of drafting on cda at 12m?
This is a question for Aerosensor or Bodyrocket and hopefully as these devices make their way onto pro bikes for races we will see these numbers solidify slightly (as well as accurate distances thanks to RaceRanger) but some experiments were done and we will head to the forums to find out what the nerds of the internet have found…
Here we found a cda reduction of 0.033 and other members of the forum appear to trust this bloke so we will take his numbers as ‘true’ because it’s all we’ve got. This is clearly not the best experiment in the world but it’s a starting point to work on the impact of drafting and as these numbers become clearer we can change our models.
Changing the cda…
So, Andy’s cda is now 0.25 when he’s on the front and 0.217 when he’s in the wheel of his mate according to some bloke on the internet – we’ll call his mate Ben. Let’s imagine Andy and Ben have agreed to do half the work each – this means that Andy’s average cda will be the average between these two values. We will assume it to be 0.233 for this reason. There’s a whole bunch of caveats at play here – for example the relative importance of cda vs other factors depend on where you are on the course but that’s partially addressed by us using the Kona course which is an out and back along a relatively flat, straight road so if our approximations are valid anywhere it’s here.
Andy is able to ride at the same average power of course as he’s turned up to the race with some given level of fitness and this is the maximum pace he’s decided to ride at while maintaining his ability to run well. Let’s check out the numbers…
Andy riding with his mate saves over 5 minutes!
Ok, so Andy saves over 5 minutes here…
What about the chase pack?
Let’s imagine there’s 4 guys all working together in the chase group trying to get up to the front of the race, to keep things simple we will assume they’re all working together equally (this doesn’t happen) and also we will assume there’s no compound effect of being 3rd in the group – ie the cda reduction the guy at the back receives is the same as the guy in 2nd (also not really true, it’s likely being 3rd wheel is easier than 2nd). This would mean an average cda for each athlete of 0.225. Again, this is an approximation that comes with a host of caveats of course…
The chase pack are even faster, saving 8 minutes on the solo rider out the front and over 2.5 minutes on the pair riding up front.
What does this all mean then?
There’s a couple of implications of these simulations and a couple of other things which need looking into. Primarily though we all need to stop pretending that Ironman bike splits can be judged without context and that non-drafting racing is actually semi-drafting. The impacts of legal drafting in triathlon are real (and we haven’t even begun to touch on the impact of motorbikes). If I had unlimited money, I’d organise the following experiment at some professional race with BodyRocket or Aerosensor (other options are available)…
Measure the cda of each athlete in isolation on the course
Plot the cda(t) for each athlete during the race and normalise against their isolated cda
This would mean that we can (assuming all the athletes are following the laws, which they generally try to do in my opinion) see where a triathlon is ‘easiest’. We will be able to answer the questions of…
How much draft do lead motos give in a race?
How much advantage is given to ‘pack rats’?
Does being a good swimmer actually matter in triathlon?
Information on tactical decisions – for example should Andy sit up and wait for Ben if there’s a swim gap?
It’s clear there’s a lot of interesting work to be done in this aspect and I’m sure the team at myWindsock will look into it in a little more detail one day.
The 2023 Tour de France stage 16 time trial has proven somewhat of a talking point. We have tried to make sense of the numbers, as at first, they seemed interesting. Essentially, we (Tom) vastly underestimated how fast Jonas would go in this TT but, with a couple of fresh assumptions, we can come up with some good (but not alien-like) numbers for the TT performance that the small Dane managed.
Where was the time gained?
During the short time trial, Vingegaard managed to gain 1 minute and 38 seconds over the Slovenian Pogacar. The TT finished with an ascent of the Côte de Domancy (6.05 km, 6.84%) after a rolling course in the earlier part. Notably, Jonas Vingegaard delivered a truly historic performance, outshining even Pogačar on the 22.4 km route by an impressive 1 minute and 38 seconds, while leaving all other competitors behind by a margin of at least 2 minutes and 51 seconds. Our, and others who have also done this, calculations reveal that Vingegaard achieved a remarkable 7.60 W/Kg for a time of 13 minutes and 21 seconds. This would undoubtedly rank among the greatest performances of all time.
Pogacar lost 77s over the course of the climb, which does include a bike change.
This plot shows how the time gap opened up minute by minute, where each data point shows the rider’s time split at each checkpoint. You can see, from the shading, that the time gap opened up much wider between checkpoint 3 and the finish than at any other point. This shows, as 79% of the time lost occurred in this sector.
The climb – Côte de Domancy
This plot, borrowed from Lanterne Rouge, shows the climbing performances of 2023 with the TT climb shown in red, Vingegaard is the red dot that appears furthest up the y-axis where it can be shown to what extent he outperformed all the other riders that day. Vingegaard must have done roughly 7.6W/kg for 13 minutes and 21 seconds up this climb according to these (and ours roughly match) calculations. This climbing performance is the best so far this year in the World Tour by some margin.
A myWindsock model of the performance
The nice thing about doing a simulation after an event has taken place is that you know the answer and your weather data is correct. We can see that Jonas had extremely favourable conditions and managed to fiddle with the settings to achieve a fairly realistic average power and cda based on what we know about the climb and the time gaps.
It was clear that Jonas’ strategy was a simple one, rail descents, ride the flat sections at a reasonable tempo and absolutely whack the last climb as hard as possible.
Inputting the power to weight estimates done as a lap on the last climb and setting the climbing pace to roughly this, we get the above power profile for Jonas’ TT. We would love for Jumbo to publish the data so we can see how our estimate stacks up! myWindsock premium features really come into their own for races like this.
The conditions
Vingegaard clearly had favourable conditions, shown with our Instagram story analysis of wImpact during the course of the day. This plot shows how Wout Van Aert’s time would have changed had he started at different points during the course of the day. This said, it’s only worth a small fraction of the time difference.
The settings we used for Jonas
We asked Ineos Grenadiers’ Dan Bigham about some realistic numbers for CRR and drivetrain resistance and, with a few caveats used the settings below as a rough estimate. In reality, especially with a course such as this one where speeds, gearing and cadence change so drastically these values vary with time but for our purpose today average values over the course of the TT will suffice.
Assuming an extremely optimised aerodynamic position and the ability to hold this almost perfectly coupled with the fact that Vingegaard is a small man these are the cda values we used. The climbing power was set from W/kg estimates and the other values were changed to fit the recorded time. It’s possible he was less aerodynamic and produced more power in the flats or descents. It’s tough to tell of course but these values produce a 30 minute average close to the peak 30 minute power shown by Vingegaard this tour in terms of W/kg.
By reducing rolling resistance to 0.003 and drivetrain losses to 2% we were able to further shave time from Jonas’ performance. The base assumption we have used, implementing myWindsock’s advanced options to do so, is that Vingegaard’s bike was perfectly optimised.
This was an extremely good ride from Vingegaard and he must have had to produce close to his peak average power for that duration in the time trial position. Something that is possible with incredible dedication to time trialing – something we know he has worked on extremely hard. From our analysis, it seems Vingegaard had a perfect day, on a perfect bike with perfect conditions and produced an other-worldly performance on that final climb. Given how aerodynamic it’s possible for a rider of that size to be and how well he descended, it’s possible he came into the base of the final climb relatively fresh. It would be interesting if Jumbo would publish his power files, as seeing how he paced this would certainly help us when predicting future performances.
If you’d like to bring a new level of analysis to your time trial performances, check out myWindsock here.
Today is the rest day of the Tour de France which has left us all sitting around and scratching our heads wondering what to do with ourselves. While I’m sure ITV and Eurosport are producing a glossy magazine show talking about some inspiring backstory surrounding Thibaut Pinot’s goats and Cycling Weekly are writing articles speculating around who feels good and who has shown ‘signs of weakness’ we decided to stay in our wheelhouse and talk about the impending time trial.
This year, the Tour has only one TT and it’s pretty short in terms of distance but that doesn’t make it unimportant. Big gaps in the general classification are possible as the course is a tricky one to pace correctly and we will see slow average speeds (relative to the usual insanity in Grand Tour time trials).
The TT takes place on Stage 16 of the 2023 Tour de France and the course goes from Passy to Combloux. It has 3 climbs, the Côte de la Cascade de Cœur, the Côte de Domancy and the ride up to Combloux to finish. The descent from Passy Chef-Lieu down to Sallanches is technical and the roads are narrow (though have been freshly resurfaced).
The parcours looks relatively flat, we can assure you that it isn’t.
The slower speeds in this climb will be interesting as will the high temperatures often seen in this valley. The teams that have invested in the materials that provide a balance between aerodynamic performance, cooling and also aerodynamic performance at slower speeds (as the fastest fabric at 60kph is not often also the fastest at 30kph) will have a competitive advantage over the riders wearing their standard speed suit. The usual disadvantage will also apply to athletes in the leaders jerseys as these skinsuits are typically slower than the team’s kit sponsor’s model.
The Weather Forecast
Due to Thunderstorms we are expecting very changeable conditions for the riders. Wind Speeds are expected to be predominantly South Westerly, at a Light Breeze of 6mph, with gusts of up to 27mph. The hot temperatures and intermittent showers will add to the complexity of the course.
On dry roads, a significant portion of the descent from Cote de la Cascade de Coeur towards Sallanches, could be taken in aero bars. However, the possibility of rain during the afternoon may cause riders to leave their fine tuned time trial positions more frequently. A wet vs dry descent is likely to be the greatest variable due to start time.
Changeable conditions with predominantly SW Wind.Average Wind SpeedWind Gusts
Expected finish times
The best place to stay apprised of the conditions on race day is via our forecast which you can find here.
Over a course like this it can be difficult to predict finish times as the aerodynamic properties of riders change a lot on long shallow climbs. That said, the TT route is preloaded into myWindsock so we can check out the sort of times we might see based on a few power and weight options.
For this kind of race, we will think of a TT specialist with a cda of 0.2 and 400W to play with, along with a system weight of 75kg then we will play with the settings to see what a rider like Pogacar – the favourite in my eyes – will do in this TT.
Run 1, the ‘average’ tour pro.
A solid benchmark for this first TT is under 37 minutes (weather pending of course). A GC contender will be able to do in the region of 6.1 W/kg for this duration and might have a slightly lower system weight of around 72kg. Let’s see what this does for the overall finishing time…
What might a GC contender do?
So the winner of the stage is likely to be pushing 35 minutes and it may come down to pacing strategy. This course also favours the lighter riders…
The force breakdown plot from myWindsock.
As you can see from our force breakdown, gravity plays a larger role than air resistance on this course – which is why I find myself frustrated when commentators describe it as ‘rolling’. This is a hilly TT that will suit climbers better. Yes the TT specialists will go better in the valley and yes the climbs are short, but the only bigger guy that stands any chance is Wout Van Aert.
What can Wout do? This is a rough estimate of what he’d need to do to be competitive on the stage.
Winning is possible for Wout – as we can see above, but he’ll need to do some monster numbers and it will need a bad day from one of the other main contenders.
Blowing up on the last climb
The last climb is steep and then turns out onto the main road where it flattens out to a low gradient for the final few kilometres. This low gradient section can be deadly though – it’s a big ring climb but it’s uphill all the way to the line. We thought we’d check out what happens if a rider cracks on this final segment by going too hard on the steep section – something we see often even in the pro peloton (think back to the final TT in 2021).
The final climb is tough with a 2.4km section over 10% average gradient.
The final climb is steep and will take riders around 15 minutes from the base to the top. The first 2.5 km is steep and the final km flattens out and goes onto a main road.
What happens if a rider blows up then?
This plot shows what happens to a rider’s time as they drop off their power. On a climb it’s pretty linear, lose 10W and you’re shipping between 10 and 20 seconds on this climb. We will see some changes on the leaderboard between the final intermediate check and the finish with this parcours.
This TT is going to be important for GC but not long enough that it will decide the race. The overall winner is likely to be a GC contender but it could be won by a rouleur on a very good day. If you want to keep up to date on the conditions on the day, follow myWindsock on Instagram where we will be keeping up to date with the fastest conditions and providing live analysis of the time trial.
If you want to have a go yourself at predicting times and winners, or want to add a new level of precision and preparation to your riding – why not use myWindsock and sign up here.
Probably not, but we thought people might google this. That said, we decided to have a proper look into it…
Echelons are exciting in professional cycling. Generally speaking, riders either love them or hate them. Crosswinds are a weird phenomenon as they can turn an innocuous piece of road into a very tricky section as riders in the wheel get no shelter if they’re in the wrong place. I find it can be a tricky concept to visualise but with a diagram (and the help of myWindsock) we can see when crosswinds might develop. Every year we see crosswinds in the classics season and the echelons occasionally pop up during grand tours. They’re exciting in grand tours particularly as GC time gaps can occur when they’re not expected.
Predicting these crosswinds can be tricky. For example, crosswinds can happen but echelons do not form due to lack of motivation. Sometimes, a team tries to create echelons but the wind doesn’t blow hard enough or for long enough. Anything that relies on the behaviour of humans and the weather can be tough to predict – myWindsock is the perfect place to check whether the conditions are right but we can’t help what people do…
What should a rider do in crosswinds?
In crosswind conditions, road cyclists encounter additional drag and destabilising lateral forces. However, cyclists have found a way to minimise these forces by adjusting their spatial formation, forming an echelon. An echelon refers to a diagonal single pace line of riders positioned in a staggered manner across the road. This configuration is distinctly different from the formations used in wind-free conditions.
In a basic configuration with four riders at a yaw angle of 50 degrees, a rider positioned within the echelon experiences less than 30% of the drag faced by the rider at the rear, who is exposed to the crosswind. Adopting an echelon becomes advantageous only when the yaw angle exceeds 30 degrees. At this critical yaw angle, the drag on the rider at the rear doubles when the distance between the two groups increases from 10 cm to 1 m in real scale. Yaw angle is essentially the effective wind angle, so if you’re riding into a headwind the yaw angle is zero degrees and it increases as we move the wind direction around the rider.
When will crosswinds cause echelons?
An echelon is only worth being adopted when the yaw angle is above 30 degrees. Cross tail winds are also more effective for splitting the peloton as the effective draft in the wheels is lower and the speeds are higher (so gaps in distance open up faster). If the wind is blowing hard from an angle large enough, crosswinds have the potential for forming echelons.
Using myWindsock to predict crosswinds
At a shallow wind angle (in the direction of a headwind) the faster the bunch rides, the closer to zero the yaw angle gets. This means that any wind blowing in the direction of a rider’s hip round to their backside is what’s most likely to cause crosswinds. As, at the time of writing, the Tour de France is on, we will take stage 3 as a ‘crosswind potential stage’. To decide whether or not a crosswind will form echelons, we need to ask a couple of questions – what direction is the wind blowing? How long is the wind blowing for? How hard is it blowing? Who is motivated to make it happen?
The first place to look is the distribution of tailwind to headwind and the directional breakdown of apparent wind direction. If it’s more tailwind than headwind and the majority of the wind is in the bottom left quadrant of the apparent wind direction graph – crosswinds are most likely to cause echelons. This breakdown is for stage 3 of the 2023 Tour de France where we can see that echelons are possible, but not likely.
The map is also an excellent place to check where crosswinds might cause splits and echelons to form. If echelons do form during this stage, it’ll be just before they turn in land toward the finish but it will require two or three motivated teams to do so as the section of cross tail wind is relatively short.
To us, crosswinds will blow in this stage but it’s unlikely to cause too much grief. GC teams will want to pay close attention as the race turns in land toward the finish where conditions are optimal for someone to try something as the wind is in the right direction and the distance to the finish is small enough that it’s not obscene to pace all the way to the line from there.
We know that myWindsock is used in many a team bus in the World Tour – so if you’ve got a bunch race coming up in a windy place (or just want to stick it to your clubmates when they don’t expect it) check out myWindsock and sign up here.
I know you all thought that myWindsock was just for time trialists – well, you’re wrong. As you might be aware, there’s the small matter of a couple of races which will decide the British National Championships this coming weekend and we thought it would be interesting to have a look at the criterium course – a 1km lap where small differences in positioning and power distribution can make outsized changes to the race result.
Mark your calendars for an exhilarating spectacle on Friday, June 23rd, as the enchanting coastal town of Redcar sets the stage for captivating circuit races. The racecourse itself spans a scenic 1km, boasting a well-deserved reputation for its intricate turns and demanding technical elements. Riders will kick off from the lively seafront, navigating their way through the bustling high street then back onto the shore front road. Prepare for an adrenaline-fuelled showdown as both the men’s and women’s races unfold, battling fiercely for 55 minutes, along with an additional five laps.
The 1km circuit boasts a total of six corners, all left handers and all relatively fast – with no hairpins or turnarounds meaning this is likely to resemble an American style criterium rather than the slightly slower traditional town centre crits in the UK. Barrier placement will play a role in how these corners are ridden but for the experienced men and women on the start line – they’ll likely still be fast.
The weather
Two factors go into a seafront crit in the north of England – one being the wind, the other is the rain. At the time of writing, we aren’t expecting rain for either race which is good news for the riders involved – the roads are relatively wide town centre roads with two lanes – these have a lot of white lines on them so the potential for slipping in the wet is very high.
Secondly, a strong wind off the seafront could cause the race to blow apart early – thankfully for some of the riders, the wind is coming from the other direction meaning they’ll be sheltered from it.
If you’d like to check the forecast out for yourself – you can do so by clicking on this image.
The interesting thing about this course is the distance from the final corner to the finish line – it’s quite big. This means riders won’t want to enter the final corner too far up the bunch or they’ll find themselves getting rolled on the line. They will have a sheltered slight cross tail (but majority cross) wind. If I was a betting man, I’d expect the winner to come from between 8 and 10 wheels back coming up the sea-facing side of the road.
If you want to race with confidence that you’ve got the best information at your disposal like riders in World Tour races and Olympic Medallists – you should do so with myWindsock by clicking here.
Box Hill, an esteemed name cherished by cyclists, resonates with profound significance. It transcends being a mere hill, evolving into a symphony of emotions, an exhilarating ballet embodying the fusion of man and machine, an awe-inspiring testament to the unyielding human spirit. Memories immediately turn to the London 2012 Olympics as the GB team train powered up there with reigning Tour de France champion Wiggins guiding Cav for a glorious sprint – which didn’t quite work out.
Approaching Box Hill, cyclists experience a surge of anticipation, their hearts racing in sync with the winding road ahead. It unfurls like a clandestine pathway to a cycling utopia, beckoning them to embark upon its mystical 5% gradient. Legs tense and muscles poised. The surrounding world dissipates into the periphery, and their focus narrows upon the rhythmic symbiosis between body and bicycle. The symphony of their breath intertwines harmoniously with the whirring of the chain, and the steady cadence of their heartbeat morphs into a metronome of unwavering determination.
The apex of Box Hill unveils a panoramic vista that steals their breath away, a well-deserved reward for their gargantuan effort. Boundless horizons of undulating hills sprawl before them, an intricately woven tapestry of limitless possibilities. In that singular moment, every ache, every drop of sweat, and every ounce of effort finds profound purpose… as your ride uploads to Strava and Rory Townsend gets an email saying someone has just nicked his KOM.
Our tips on sending Rory Townsend an email
Box Hill means a lot to cyclists in the UK – not as much as it used to but the KOM is still a big one. All Strava nerds know who holds it and we are going to advise you on how you might go about trying to take it with the help of myWindsock.
This 3D veloviewer map allows us to visualise how the segment of box hill will play out when we ride it.
As I’m sure you can imagine, there’s a large number of segments on Box Hill but this map gives us a good idea of the main features of the climb – namely that it’s not particularly steep. This means aerodynamics plays a large role. Box Hill is a particularly interesting segment as pretty much all forces play a significant role in slowing you down (whereas usually either weight or aerodynamics are overwhelmingly dominant).
We are still going up a climb, however, so as you can see gravity is the strongest resistive force. The rolling resistance and air resistance make up over 20% of what is slowing us down; however, this means that for every 100W we put through the pedals, 20W isn’t doing work against gravity.
The elevation gain on this segment is 118m which means we need to do 92575J of work against gravity to get to the top and there’s nothing we can do about this. In order to reduce the amount of energy lost to the other resistive forces, we have three main strategies…
Drafting – if you’re behind something big enough, air resistance can be practically zero. I recommend a car with the boot open in front and a van behind. Obviously, if you do decide to take this route, don’t do it on a busy day…
This shows us the huge difference that drafting can make. By sitting between two relatively large vehicles a rider could get their aerodynamic resistance relatively close to zero. It’s been measured that a rider in the middle of a peloton faces around 5% of the air resistance a rider on the front would face – so it’s not too different from that, possibly a tad more dangerous.
In reality, you won’t be able to get your cda down to zero but you probably can get pretty close if you’re willing to risk your life. For a rider (and bike) that weighs 80kg doing 400W, removing air resistance is enough to take the KOM.
2. Fast tyres – using myWindsock’s advanced settings we can change the rolling resistance and drivetrain losses. Imagining we’ve splashed out on all the latest tech and halved our rolling resistance and dropped our drivetrain losses by half a percent, we can save ourselves 13s.
3. Weight loss – it’s likely that we won’t be able to lose weight ourselves, but let’s imagine we are a 70kg rider with 6kg of extra baggage (bike, clothes, shoes and such) so we can drop our system weight down to 76kg from 80kg. This is another 12s saved.
Overall this trickery has taken our time down to 4 minutes dead. The KOM is currently at 4:32 so if you want to take the box hill kom and don’t have many watts, simply cheat and buy very posh bike parts.
If you want to know how much difference various factors make on your own personal segment bashing quests, sign up to myWindsock here.
UK Time Trial Events
.jpg)
