Crash Bang Wallop

I’ve only managed to catch some snippets of the Giro until this point (the morning of the first individual time trial), it’s already proving to be a very interesting race, plus it’s currently completely unpredictable who will take final victory.

We’ve got hero’s & villains, wet roads, inclement weather, crashes, short steep climbs, we could be in Scotland! His Nibs is on the attack whenever possible, Wiggo has a potential hidden stomach problem as tweeted by his old DS, Jonathan Vaughters (@Vaughters on twitter) “my guess? BW has been suffering w same stomach issues as Cataldo, but they’ve kept quiet about it. Bet my balls on it.

So if that is the case, we can presume that Wiggins may not take the expected victory margin today, but we can still assume he’ll not lose anything, then we’ll get a rare chance to see what he can actually do in full attack mode later on, with his Colombian security guards in close attendance he’ll have to take this race by the scruff of the neck if he hopes to win it. The Giro could just be kicking off, with the stomach illness a catalyst for a spectacular Giro for the fans, but a nightmare for stage race aficionados Team Sky.

The other riders looking good are Nibali, Evans lurking near the front, Gesink’s team with full confidence in him, 2012 victor Hesjedal looking great. There’s plenty of my favourite villains up there too, Suzanne, Dirty Sanchez, Danielson, Scarponi, Pellizotti etc, it a perfect mix & lets face it, we love shouting at the telly when some of our least favourite riders are attacking.

Hopefully we’ll get to see it at a more suitable time on Eurosport soon, it’s the bloody Giro, it should be prime time!

My name’s Di Luca, I live on the 2nd floor.

Twitter breathed a sigh of dis-contentment this week when 2007 Giro winner Danilo Di Luca was seen attacking on the finale of stage 4 at the Giro, it brings back memories of an era we were all trying to forget when we see Di Luca going well, we only assume one thing.

Why the blog title?

The lyrics for Suzanne Vega’s song ‘Luka’ fits our rogues name nicely, it also helps us explain to some extent his actions, his state of mind & his justification for the various scandals we know he’s been involved in, plus presumably many we don’t (yet) know about. I’ll start referring to Di Luca as ‘Suzanne’, I think it’s a nice name for him. Here’s a link to the lyrics.

The song is about domestic abuse, from somebody talking silently to somebody else who lives close to them, who knows you can hear what’s going on in their flat, but doesn’t want you to interfere, for whatever reason that may be. I’m likening Luka’s ‘significant other’ to Di Luca’s doping, only in his case, he does actually have a choice, unlike ‘Luka’. Suzanne loves his drugs, he’s been involved in several investigations, here’s a few…

2004: Oil for drugs investigation. Wikipedia information.

2007: Abnormally low hormone levels.

2007: 3 month doping ban.

2009: Tested positive for Cera EPO during the Giro.

2010: Admits to being a doper.

So Suzanne is a proven & banned doper, his previous best results were during a period he admitted to doping, so it’s hard for fans to believe that he can perform at the top level without drugs, that’s why when we see him attack the best riders in world we all tweet a sigh of discontent, even @BriSmithy exhaled in disgust. It’s really is ‘not normal’.

Suzanne’s history is littered with a love for his abusive ‘significant other’, an addiction he knows hurts him but he just can’t keep himself away from it. We all like to marvel at ‘panache’ and the ability to attack in the mountains, but in almost every one of the years we marvelled at Suzanne, there were questions about where that ability actually came from. Sometimes drugs look like panache & the attacking riders we loved to watch were not naturally capable of what we enjoy seeing them do. I can only hope that he doesn’t win a stage, I’m fully aware that there are plenty of others similar to him still riding, but this fella really irks me. He’s been rubbing it in everybody’s face for a long time and always seems to get a chance to return to the peloton, again on a team that doesn’t have to adopt the bio-passport, it’s disappointing for fans like myself to even see him there.

It really wouldn’t be any surprise if Suzanne was the Grand-Tour winning rider the Secret Pro was referring to as the rider caught up in a bio-passport infringement “I can’t say who it is but when the news breaks you’ll know who I’m talking about”, only time will tell.

Another rant, why can’t I watch the Giro on Eurosport before it’s my bedtime, I really want to watch the Giro!

Giro Air Attack Data

I found some information regarding some of the daft helmets in my previous post HERE. Getting power outputs from this requires a small amount of schoolboy maths, so here it is for one of the silly looking helmets on the market.

The maths

Giro have published their drag in Newtons (N) on their website, you can get to it through the following link. Giro Air Attack, then looking at the COMPARE tab. this shows you the difference between the new Air Attack & the established vented Aeon helmets, which is reasonably aerodynamic looking in itself. But if this data is accurate it should give us a good estimate of the power saving that Giro sponsored teams get by using the Air Attack over a standard Giro vented helmet.

The figures are at 25mph or 40kmh, the Aeon has a drag of about 4.2N, the Air Attack approx 3.7N. The drag will increase significantly as speed increases, this isn’t linear, so going twice the speed produces much more drag than a multiple of two, here’s the figures.

25mph/40kmh

Aeon: Power requirement is Force X Velocity. 4.2 (N) X 11.176 (m/s) = 46.9 Watts

Air Attack: Power requirement is Force X Velocity. 3.7 (N) X 11.176 (m/s) = 41.4 Watts

So we see that at 40kmh, our pro riders are saving approx 5 Watts of power by wearing a silly hat. Now lets look at what happens when we consider sprint leadouts & other high speed situations at 80kmh.

50mph/80kmh

We are not given the drag forces at this speed, so we’ll have to do a calculation to determine CdA, which is the coefficient of drag X area, we just need the value so it can be approximated by using the 25mph figures as follows.

F = CdA X p X (v squared / 2)

F = Force i.e. our drag value in Newtons.

CdA = Drag coefficient X area

p = Air density in kg/m3

v = Velocity in m/s

At 25mph we have F, p (normally approx 1.225 at sea level) & v (25mph is 11.176m/s). So to save you a headache, I’ve calculated CdA as the following.

CdA Aeon = 0.0549

CdA Air Attack = 0.0484

So using the same formula we can alter the speed and we now find that the drag on each helmet is as follows:

Aeon:

Drag = 16.6 N

Wattage required = 16.6 (N) X 22.222 (m/s) = 369 Watts

Air Attack:

Drag = 14.6 N

Wattage required = 14.6 (N) X 22.222 (m/s) = 325 Watts

Conclusion

We can see from the above that power requirement is huge at 80kmh compared to half that speed, approximate savings at the lower speed are about 5 Watts, while at the higher speed we see about 44 Watts. We can assume that most sprinters & lead out men require over 1500 Watts. The above calculations are solely for the helmet, not the total power requirement, so we can see how a series of so-called ‘marginal gains’ will produce a few watts here, a few watts there and you see why the sprinters & lead out men are using any aero benefit they can to deliver their sprinter to the front at as high a speed as possible. Also bear in mind that these are all estimates, but likely not particularly far away from the actual wattage savings. As I said before, silly hats are here to stay, in fact they may get even sillier until the UCI steps in.

Subsonic Flow

There’s been a lot of chat about Gorilla Greipel’s new chrome dome helmet, but lets look at the facts and come to the understanding that these are here to stay, especially in the northern classics & more generally in colder climates like ours.

A bit of History

Proper polystyrene protective helmets began appearing the very late 80’s in Scottish racing, they became part of the rules in about 1991 & the old foam & leather ‘bunch of bananas’ or ‘hairnet helmet’ became confined to history forever. The very early helmets were a little bulky, but then Giro, Specialized and a few others developed some good looking (at the time) lids and things moved on from there. Greg Lemond was an early pioneer and trailblazer of everything aero, likely prompted by sponsor pressure too, he promoted Giro helmets and used a very early closed vent version of the ‘Air Attack’ model called the ‘Giro Track Attack’ which reputedly had a 5% aero advantage over a bare head, although nobody was listening back then (things have gone full circle now and a new ‘Air Attack’ now exists along with a development ‘Track Attack’). Meanwhile the pro’s were regularly sitting at the side of the road protesting about having to wear the things, while us amateurs were just getting on with it. Things changed, the pro ranks were allowed to discard the lids on the last mountain of a stage race, then eventually they had to wear them all the time, that’s where we are right now.

Some Technicalities

You can understand to some extent what the pro’s were annoyed about, early helmet technology had resulted in some not particularly well vented examples, they had to wear what their sponsor gave them, so helmet choice/luck became part of the game. Helmets then became increasingly vented to keep the top riders happy, those riders needed them to have enough airflow over their head for 50 minute climbs in 30 degrees heat a low speeds. All the adverts were stating the amount of vents, as if it was the key selling point to ‘normal’ cyclists.

Now consider your average Scottish race, you’re unlikely to be climbing many hills over 5 minutes, at most it’ll be 10 minutes climbing, temperatures on the warmest day are 25 degrees one day a year, but likely you’re racing in an average of 15 degrees, punching over small hills at a reasonable speed. Do you really need as much airflow as the 50 minute, low-speed, 30 degree heat boys? Of course not, don’t kid yourself on.

This brings us to ventless aero helmets for road racing. They currently look ridiculous to us, but so did all helmets when we first saw them, maybe we’re just not used to them yet. The Sky team have been using them for a couple of seasons with their Kask helmets. Although these ones show the vents and retain the look of a vented helmet to some degree, although the yellow ones were ridiculous. So we have a half way house here, some manufacturers are trying to retain a vented look, while others like Lazer are going full aero, which is the likely outcome over the next couple of years. The vague vents will slowly disappear in order to become more aero, the UCI will change the rules and stop everything becoming too aero and un-Merckx like. So we have a hidden race, between an acceptable look and the desired function, to go faster. Greipel’s claimed sprint max speed was 74km/h in one of the Tour down Under stages, so how much advantage did this aero hat give himself and his team, with Henderson dropping him off into the final sprint at his claimed 70km/h? There’s obviously no data out yet, but Cavendish’s worlds helmet cover on his Specialized lid will explain that it’s a measured ‘marginal gain’ and worth enough watts to encourage manufacturers to develop products. You’ll hear terms like ‘subsonic flow’ ‘boundary layers’ & ‘turbulence’ being banded about in marketing material, it’ll all become very technical, they’ll all claim to be the fastest.

Helmets for Scotland (or anywhere cold)

Do we need all these vents, as explained above, we don’t. So as you’ll see in the northern classics from now on, non vented helmets will become prolific, even more so in cold markets like our country. If pro’s can wear non vented helmets in stages of le Tour, if we’re honest with ourselves, we could wear them all year round. Especially in winter, they would probably make a significant difference with reduced airflow and nice warm head. We’re currently wearing helmets with 20 something vents in minus temperatures, there’s no logic to that. It comes down to aesthetics, vented helmets look correct right now, only because since 1991 we’ve got used to them, previous to that anything other than a hairnet, a bare head or a cap looked right. Times change and in 5 to 10 years time, once there’s plenty of pro photos out there of top riders saluting the crowd in an aero road race helmet, you’ll think aero road helmets are the thing to wear in the bunch or training ride.

The future of headwear

Expect Assos & Rapha to ‘develop’ breathable under-aero-caps to complement your new fast lid, where there’s a marketing opportunity, there’s the momentum to make anything stick. Aero, ventless road race helmets, you’d better get used to them, they’re not going away, in fact, they’re probably a good idea in Scotland, you’ll get used to how they look.