Wednesday, March 29, 2017

Why Testing is important - The Outliers

Another theory blog? It looks like it. Seems like lately I've just had a lot of heavy stuff coming down on top of me that needs put into words. (Heavy for bike related stuff, not real life stuff)

If you like to nerd out on bike stuff (and, if you are still reading this blog I assume that has to be at least relatively true) then I'd say there is a very, very good chance you have either googled, posted on a forum or asked a friend / competitor "what is the best xxxx." Whether xxxx is helmet, shoes, bike, wheels, tires... whatever. And you almost certainly got an answer... more likely if you asked on a forum you got a LOT of answers, and a lot of contradictory ones as well.  Now, the overwhelming majority of those answers will come from a place of "I use/like this so I recommend it" or, slightly better they have read and regurgitated that x piece of equipment regularly tests better than y. Very few have actually done testing, of those even fewer have tested on a sample size other than themselves, and none have tested that piece of equipment on YOU.

So, you will find yourself at a crossroads with three possible paths to take.

  1. Just pick the one you like the best. This one requires the absolute least work on your part... and nonetheless, this is often a suggestion even I give people, because when it boils down to it if you are spending your hard earned money on this or that piece of kit, you have to like it. Buying a much faster aero helmet won't do you any good if you don't pick it up to use it in races because of whatever reason that "really" boils down to you not liking it.
  2. You do some research and pick the one that seems to be "best" on the most people. This is really just playing the odds and hoping that you are NOT an outlier. It requires a bit of effort on your part as you need to dig through quite a bit of information to find these kinds of things. A good example is aero helmets... most of the modern Giro helmets test very well on a wide variety of people, so it's a safe recommendation if you are in the market for an aero helmet to just pick up the one you can afford (A2's run under $100, Selectors a slight bit more and Aeroheads in the mid $200's) and bank on the "it's good for more people than it's bad for" odds. You obviously don't "know" you fit into that category, but it's probably the best you can do for a guess.
  3. Personal testing. There are many methods of individual testing, and when it boils down to it, most of them are relatively effective at giving a clear answer as to whether A or B is better. These methods each have their own benefits and negatives and can wildly vary in cost and accuracy. The "gold standard" is of course the wind tunnel, where you'll spend a couple of hundred dollars per hour but will get an accurate number with the minimal amount of heavy lifting required by you. There is velodrome testing that ERO and Aerocoach have made popular as an alternative to tunnel testing, generally a bit cheaper but with slightly more variables. Then there is the "at home" testing, the (currently) best of which is the Chung method. This will require at least a little work by you to figure out how to actually sort through the data, and you'll need a (accurate) power meter, something most of the semi serious athletes will already have access to. Seemingly the hardest part of Chung testing is actually convincing someone to take the time to go out and do it. If a power meter isn't in the budget, there is always the old fashioned rolldown test... which doesn't take any "extra" equipment other than a friend, a stopwatch and a hill... and the patience to do many, many repeats to try and eliminate botched data. Some of the old school guys used to take pictures from the front then cut out their silhouette and weigh it to measure frontal area (now much easier with something like photoshop) although frontal area is limited in what it tells. 

Personal testing is great for everyone, but it's especially important if you are the outlier. (See the circle of life coming together here? How do you know you are the outlier...) For most people, I think the Rudy Wing 57 is not a terribly great choice for an aero lid. Nonetheless, Rudy 50% discount codes abound and it's a very popular helmet. Most of the people I help with their testing find that the Wing57 is not great for them. On the flip side, the Aerohead is consistently the #1 helmet for folks. So it's my go to suggestion when people blind ask "what helmet." Nonetheless, an athlete just this weekend tested them head to head... the winner? The Wing57. In this case, If she had went with option 1 or 3 (which she did) she'd have gotten the best helmet. If she'd listened to me (option 2) she'd have picked a slower helmet. So you can see the dangers in randomness and in taking someone's (even good) judgment as truth.

I really got this reinforced into my head at the wind tunnel this past trip. I had a custom Nopinz supersuit that I had ordered last year that I had been wearing in my A-races. The thing was very difficult to get into, so I never took it out to my loop and field tested it, I just assumed it was a great suit. When I took it to the tunnel... I was giving up about 10 watts vs. my "backup" Castelli Bodypaint 2.0.  I was shocked. So every time it really mattered in a race I was penalizing myself 10 watts. Even the pastor needs the gospel reinforced to him every now and then.

Thank you guys for reading! I really appreciate it! Now go test!

- Christopher Morelock

No comments:

Post a Comment