When I arrived at the A2 Wind Tunnel, I was ready to listen and learn. This team at the tunnel had recently hosted Craig Alexander, Mat Steinmetz, and the Specialized team – the best thing I could do was ask intelligent questions and soak it all in. They were going to tell me real answers to all those hypothetical questions that I had posed during my helmet research. Dave Salazar, the manager, and Jim O’Brien, the bike-fitting guru, were on-hand to walk me through the process and answer all the questions that I had (which were a ton). They got me set up in the tunnel and had me begin to spin so that Jim could take a look at my present position to determine some adjustments that could be tested. While my #1 goal was to find an aero helmet, I knew I had an opportunity to make some tweaks in the position. After the warm up, we needed to develop a baseline from which we would compare/contrast all other tests.
Now, this goes without saying, but each individual is affected by the testing differently. And while thousands of know-it-all Slowtwitch users can pontificate on the best helmet on the market or the ideal position, your specific characteristics drive your needs. I can’t stress that enough as I go through my own individual results – the information makes sense for me, but may not even be remotely similar for many others.
|Baseline Test. Game Face On. Obviously.|
First and foremost, the wind speed was tested consistently at 30 mph. Second, as you can see from the data above, there are numerous metrics that were measured. Many people understand CdA and drag grams. For this article, I am going to focus on “Aero Watts” as it is easiest to conceptualize. With that in mind, focus on the “input MPH = 23” on the upper right corner of the table. You’ll see that my MPH is set at 23, which is approximately my average speed in most of my 70.3 efforts. Simply put, the “Aero Watts” is a measure of the power that is necessary to produce 23 mph on a flat course. With the baseline, I was looking at 186-188. There was definitely room for improvement.
In case you need a clear interpretation, my road helmet is aero death. I did not move one millimeter on my position, and still both aero helmets dramatically improved my position. The Giro Selector (Test #2) is the newest addition of Giro’s aero line and an “upgrade” from the Advantage (Test #3). The Selector was a little more difficult for me to get on quickly, and had significantly less ventilation. While this contributed to the better aerodynamic numbers, it was the only helmet that made me sweat significantly during the short test. The Advantage was a little cooler and did not have a built in visor, but it came in testing a bit worse (181 to 176).
|...but not fast enough|
|Not everyone can be like Fabian|
While Cancellara displays a great position for a long-tailed helmet, you can easily understand that I do not. It is difficult to see from the side view, due to the white back of the jersey, but if you look closely at the overhead shot of the Selector you can tell that there is a decent gap between my back and the tail.
Luckily for me, the A2 tunnel actually received some helmets from Kask to test just before my appointment. One of these helmets was the Bambino, made famous during last year’s Tour de France by Team Sky and eventual winner Bradley Wiggins. With its unique design and short tail, it became the next tested helmet.
|Now we're talking|
|8 months later; still not impressed|
|Still missing something|
The picture to the left shows a slightly better back angle with lower stack height, and yet – and much to my surprise – there wasn’t much difference at all. Now, I will admit that I need to do a better job of working on head position and that also can help reduce drag. But as you’ll see in a moment, even with “head position awareness” there gain wouldn’t be significant with a smaller stem.
We conducted another test with the Selector to see if anything changed (it didn’t). We then raised the stack height back, kept other changes (aero bar extension and pad width), and tested two more times with the Bambino, the final test focusing on “head position awareness”.
Free speed was mine! I dropped 18 aero watts from my worst run to my best – with an aero helmet and a few small tweaks. Crazy right? Most importantly, I now had confidence with data back-up to know that I was in the best position possible to get the most out of my physical ability – nothing wasted. Free Speed.
Free speed isn’t exclusive to me, you just have to read Haycraft’s blog, understand that aerodynamics are specific to the individual, and, you know, marry a significant other who “gets” your crazy hobby and gives awesome gifts.