Tunnel Vision
Tunnel Vision
MAIN CONTENT
For the last year or so, Brian, Heath and others have been getting on my case about finding time in the wind tunnel. I really wanted to do it—it's a good investment and huge potential for time saving—but I couldn't help it when a little imposter syndrome kicked in.
"Maybe when I finally break five hours in an Ironman bike," I thought to myself. "Maybe then it will matter." Or, even better, "But I'm still X pounds or so above race weight... why drop some serious cash when I could just clean up my diet and see the same results?"
But as I've started spending more time evaluating my current vs wish-list gear and riding with roadies who will go so far as to point out the watts-saved by not cross-chaining your gears and being OCD about a clean bike. So this winter I decided I would take the plunge. I have always been strong on the bike but always with the feeling that I was giving away free speed with my current set-up and gear choices.
Plus, I will never turn down the opportunity to hang with two of my favorite people, Brian and Heath. I had spent the previous few days in Boulder training for my new job (slash sneaky altitude training) and barely made it back to NC via red-eye flight with an hour or so to spare. Needless to say, I was a little delirious and tired, but excited to get into the tunnel.
Brian and Heath had me show up with my full bike set-up and the gear that I would normally race in, with the exception of my Alto Cycling wheels—since they are an obvious upgrade for my 2016 season! From there, we added and removed and swapped out items and would run the new set-up each time to see the differences in drag at 1) head-on and 2) at yaw.
The trick here is incremental changes. So sometimes it was frustrating to change 1mm of spacer and see that the difference was negligible or, even worse, creating an increase in drag! I got in 18 runs and tried a number of bike set-ups, helmet options, kit options and bottle placement. The amazing thing is the sheer amount of gear Brian/Heath/A2 had on hand to test for all of the athletes. However, the one other thing about the wind tunnel that they don't tell you is that you don't get a nice little change room when you're making gear swaps. You get to stand outside in this giant warehouse and get stark naked (well, in my case nothing but a POC helmet) while you hope that despite being videoed non-stop inside the tunnels, there are none outside...
Yep, just change right here in this giant warehouse next to a pile of helmets
BUT BEFORE WE BEGIN, A PRIMER ON TUNNEL TESTING:
You pay by the hour so you better have your gear all set coming in and have somewhat of a plan of action. Of course Brian and Heath are pros so they will have more than enough recommendations to get you going.
On that note, also make sure your bike is tuned up and in working order. To quote Heath, "Do as I say, not as I do", people.
You will get as many runs in as possible but the number depends on what you need. Lots of elaborate changes to the bike that require wrenching? Probably not as many. Trying on all 20 helmets they have on hand? Probably more runs. Again, depends.
You will hold to pause head on, facing the fans, before the "wind" turns on. This means no moving. There will be a signal, the fans will come on and then you'll pedal straight-forward/head-on for a minute or so and then the platform you're standing on will rotate you and your bike. You'll keep pedaling and do the same at this slight angle. The whole time you are trying to stay controlled and consistent, and not move your torso around or shift in your seat or bobble your head side-to-side. This is important!
The head on angle is 0 "Yaw" (layman's: "wind angle"), while the slightly rotated is at 10 "Yaw" or 10-degrees rotated from head-on. This provides additional data-points since we're never riding directly into a head-wind at all times (well, I hope not - that would suck).
Typically all runs are done at 30mph, industry standard. While I could never hold 30mph, it's really just to tease out the smaller differences in testing that are harder to see at a more realistic speed.
For the subsequent run, you will only want to change one thing. Yes, this starts to get tedious but the point is to keep all things constant, except for the one update being tested. Otherwise, if you swap out five things, how do you know what was providing the most significant boost? You don't. So you keep things scientific.
Rinse and repeat, as many times as possible.
You then get a crazy ton of data, that A2 drops onto a CD drive for you and sends you home with to make more informed decisions about your bike set-up and gear. Cool? Cool.
And let's not also skip:
SOME BASIC WIND TUNNEL TERMINOLOGY
• 0 Yaw: wind coming at you head-on
• 10 Yaw: wind coming to you at a slight angle
• CdA: coefficient of drag, or the air resistance attributed to an object based on drag * frontal area.
If you find all of this very cool or even just mildly interesting, I highly recommend the following pages to better educate yourself:
• http://www.aeroweenie.com/data.html
• http://www.cyclingpowerlab.com/CyclingAerodynamics.aspx
Now some personal highlights:
RUN #1 BASELINE
What I would normally wear in a race—exactly the same as my 2015 set-up, but with the addition of Alto Cycling Wheels.
• Bike set-up: semi-aggressive position
• Kit: Smashfest top, Zoot Shorts
• Aero-top: Castelli Stealth Top
• Helmet: Giro Advantage Aero Helmet
• Two bottles on frame: one on down-tube, one BTA
I finished and got the "this is not good" look from Brian, who basically told me I had terrible numbers and was the equivalent of a flying brick. Some people would hate to hear this but this was the best news I could have hoped for... lots of room for improvement and an investment well worth it! Keep reading to hear the total potential time savings!
Baseline outfit.
RUNS #14-15 AEROKITS
I also knew going into this that I wanted a true aero kit and had been lusting after the new Cuore kits and Heath's custom Cuore kit for the last few months. While the Castelli top does a pretty good job, it's a pain to get on post-swim and I don't like having all the layers while racing. I knew the Cuore kits perform excellent and look great and lo and behold it was even more amazing when I tried both on—the women's cut was more comfortable than my favorite pair of pajamas: incredibly light and soft and clearly breathable. Honestly folks, I could sleep in it.
I first ran the Women's Small, which performed WAYYY better than my previous baseline of tri kit/Castelli top and the 0 Yaw would be one of the fastest data points of the day. I also tried on the Men's in the extra small but no big differences there either. I'm currently working to get the Cuore women's two-in-one tri kit. I am SO excited to have found something so breathable and yet so fast (and cute—again, priorities!)
The Women's Cuore Suit
IN SUMMARY:
Finally, I think these graphs are the most telling. You'll probably have to click into each to read more details:
Here you can see how each incremental change led to decreases in drag for the most part. Basically, each drop indicates a huge fist pump and me exclaiming to Brian and Heath, "I can't believe it—this is so freaking awesome!"
You might also notice that some of the test scenarios in the first graph aren't displayed here. Basically if they were testing so poorly at 0 Yaw, there was no point in continuing to test and they would shut off the fans.
This last one is the CdA at 0 (Blue) and 10 (Red)—you can clearly see those that peformed better and how I made some of my gear choices based on the feedback provided. Even better is the fact that I have done New Orleans 70.3 twice before and will be heading there in a few weeks with the new set-up. I am pretty sure I will be reporting back with some feedback on the new position and gear tweaks, along with a very fast time!
I have some other cool numbers and charts but I think you get the basic idea. However, if this is up your alley or something you are considering, I am definitely happy to share more or talk more in depth about the experience/results—just let me know!
One thing I can't reiterate enough is that while the results here are definitely insightful, what works for one person doesn't always work for another. One great example: last year I purchased a Giro Advantage Helmet on Brian's recommendation that it "tends to" work best for most people, but looks like i found some others that work even better for me—testing is pretty much the only way to confirm it.
The most exciting thing about the whole experience (I mean, other than the excuse to go gear shopping!) is that you can estimate potential time savings based on your reduction in drag. For example, if I ride the same effort/speed for the Ironman distance, the tweaks from my time in the tunnel should have me riding up to...
TWELVE MINUTES FASTER
That alone would have put in me tenth overall at Ironman Chattanooga or riding a 5:04 at hilly Ironman Mont Tremblant.... Free Speed Indeed! Between these savings and getting kicked in the teeth by the big boys each week at the local Saturday 4hr ride/Wednesday night crit, I cannot tell you how excited I am to have some screaming bike splits in 2016!
Thanks for reading, hope you found it interesting and/or useful in some way!