The Win Tunnel: Shaved and Dangerous?

Shaving is a long standing rite of passage in road cycling. Before you roast me in the comments for that statement, let’s reflect back to a review Zach wrote last year, where you lambasted him for unshaven legs (and bro socks). Style aside though, are shaved legs actually faster? Specialized decided to take it to the wind tunnel. Hit play to learn the amazing results.

Have questions? Post them to Specialized’s Facebook or Twitter account with the hashtag #AeroIsEverything and you just might get a response.

Comments

Matt - 07/01/14 - 9:55pm

Calling BS. There is no possible way this means anything aside from the fact that cyclists are nerds/snobs and should spend more time worrying about riding versus what, how, with who and why they are riding. Do WTF you want. Screw everyone else’s opinion.

godisdead - 07/01/14 - 10:13pm

Does this mean the end of hipster beards?

Brattercakes - 07/01/14 - 10:16pm

Ok, now they need to use a non-specialzied wind tunnel.

Rico - 07/01/14 - 10:20pm

Matt, what exactly does that statement mean? What I heard in te video was a minute and a half over 40km. What are you calling BS? And how are both you telling people to have their own opinion while also calling this info BS. I’d bet you were one of the guys who always said it was stupid or gay to shave. Don’t be insecure about this topic. Even MMA fighters shave their body hair and they also paint their toenails.

Hotep - 07/01/14 - 10:29pm

I’ve been saying this for years. It’s faster. I’m faster. Go Faster Now. Shave yer pegs.

zombieweekly - 07/01/14 - 10:32pm

AYHSMB, I won’t shave my legs. Just can’t stand the itchiness…

J - 07/01/14 - 10:35pm

This unbiased study brought to you by Bic

anonymous - 07/01/14 - 11:20pm

@godisdead
They already did that one.

No one is forcing you to shave. The fact that you feel so threatened and defensive simply reflects your insecurity. People feel the same way about skintight lycra, which has a very significant difference.

Meh - 07/01/14 - 11:21pm

Next study: shaved heads will make you go faster.

wheelz - 07/01/14 - 11:22pm

Dang. I’m also shocked that it makes such a big difference, but more than a minute saved on a 40 km/h effort is too much to ignore if I’m racing seriously. I got lazy with shaving this year, but looks like I’m going to have to start again. Very informative video!

esc8engn - 07/01/14 - 11:33pm

RITE of passage. *ahem*

Psi Squared - 07/01/14 - 11:34pm

Cool. I can’t really see where the bias would be here, especially given what they stated about their procedure. They even admitted the shaving for that rider saved more time over the given distance than what they claimed the Venge would save.

Scott - 07/02/14 - 12:03am

What I do not get, is when they tested Beard vs. No Beard, they claimed it made almost no difference. I don’t understand that. Is it because the head stays relatively stationary whilst the legs are in motion?

David - 07/02/14 - 12:15am

The posts on that shoe review were hilarious. A bunch of dudes getting bent out of shape because another guy doesn’t shave his legs. Amazing.

anonymous - 07/02/14 - 1:18am

I want to see them do a ponytail test. Everyone knows Lemond won the 1989 TdF because of aerobars, was it was thrown around afterwards that if Fignon cut off his ponytail, he would have won.

He lost by 8 seconds during a ~25km time trial.

J Gunther - 07/02/14 - 2:44am

Yes, so 82 seconds over 40km distance but at what SPEED? Aerodynamic drag increases exponentially with speed. The data is useless without knowing what metric you were using. From 1:51 on the video the monitor shows 49km/hr so 30 mph. How much of a difference does it makes for those of us who aren’t going as fast as time trialists?

Jack - 07/02/14 - 3:03am

Fignon lost the 89 TDF to LeMond because he (Fignon) had a mother of a saddle sore and could not sit properly on his bike

anonymous - 07/02/14 - 5:00am

@jack
Fignon lost for various reasons. Saddle sore, thinking he had it in the bag, competitor using illegal equipment, pony tail, etc

@j gunther
This is common knowledge. The slower you go, the more time you save. While the savings is proportionally less, the time savings in absolute terms is greater. So you will save more than 82 seconds.

Here’s some numbers from bikecalculator:
100w in the hoods takes 80min to go 20mi
100w in the drops takes 74min to go 20mi
500w in the hoods takes 44min to go 20mi
500w in the drops takes 40min to go 20mi

So the guy pushing 500w at ~30mph “only” saves ~4min by switching to the drops but is ~9% faster, whereas the guy pushing 100w at ~15mph saves a greater ~6min by switching to drops but is only ~7% faster.

Chris - 07/02/14 - 5:10am

@J Gunther Great question, we actually get that one a lot. We usually have the fans running at 50km/h to make the measurements as sensitive as possible but the data that we record is basically like a drag coefficient, which is independent of speed. We then can calculate savings at any speed. The 82s quoted is at 40km/h, BUT you actually save more time over a given distance if you go slower. It’s counter intuitive but you’re out there for longer when you’re going slower so there’s more opportunity to reap the benefit, even though the benefit at any given instance is smaller…if that makes sense. Either way the range of saved time is +/- a few seconds over a pretty big range of speeds, so it’s pretty relevant to everyone. That’s why we’ve chosen to show our results in this form rather than, say, watts.

H M - 07/02/14 - 8:30am

Next step – shaving arms….

JTrain - 07/02/14 - 8:32am

And here I was just about to drop my life savings on a new Venge, only to find out that shaving my legs will do the same thing! Time for that vacation to Aruba.

pmurf - 07/02/14 - 8:50am

JTrain right!? I’m surprised Specialized let him say that on this video. Not exactly a great marketing move, haha. I guess we know these videos are objective.

groghunter - 07/02/14 - 10:31am

and here i thought people shaved because hair in road rashes is miserable.

Greg - 07/02/14 - 10:33am

@jack, if I recall correctly, Fignon still finished 3rd in that time trial. Not a bad result for someone suffering from a saddle sore. He lost because not only was LeMond faster and more motivated that day, but also because LeMond had the advantage of aero bars and an aero helmet.

@anonymous… “illegal equipment”? Just because LeMond was the 1st to use aero bars in the TDF doesn’t mean they were illegal. Or were you referring to something else?

Durishin - 07/02/14 - 11:26am

So what gains from shaving arm hair?

Derek - 07/02/14 - 12:02pm

@Chris

Are you going to post a paper or any more info on this? It would be interesting to see a picture of the rider’s legs before shaving and how much time each shaved.

anonymous - 07/02/14 - 2:46pm

@greg
The point is Fignon lost by a small margin which could have been improved through a number of various factors. Given the obsession with wind tunnels and hair, the pony tail.

Topmounter - 07/02/14 - 4:03pm

I think you’re supposed shave your legs AND buy a Venge. This article should be published in Hipster Cycling and the title should be “Shaving: No longer just for balls”. I used to favor periodically shaving my legs, but I don’t do so much road riding nowadays and prefer not to reek road-dork so much while riding trail.

Chris W - 07/08/14 - 2:46pm

@Chris so it’s better no matter if you’re trying to save watts, go farther, or ride longer. The more time you spend, the more opportunity to reap the benefits. Yes?

@pmurf seems to me like great marketing. I appreciate open and upright companies.

@annonymous it’s almost as if Fignon’s loss became a case study for Sky’s model of marginal gains.

OGS - 07/15/14 - 12:40am

So the claim of 80 seconds savings over 40K time trial (at 40K per hour, or 25mph) means velocity is 2.22% higher, at the same power. Since power is proportional to velocity cubed, at these speeds most of energy is spent against air resistance, this means 6.8%, almost 7% power savings. So if one was riding at 300W, shaving saves you 20W?! That doesn’t sound crazy to you guys? Crazy enough to run some more controls?

If you imagine overall frontal area that contributes to drag, a few hairs on legs (or arms for that matter) will not even make up for 0.7%, never mind 7%. I realize it’s not just frontal area, there’s turbulence and all that, but still, 7% is too high to be believable.

Sheldon Brown references research that reports 0.6% savings, which sound about right to me.
http://www.sheldonbrown.com/rinard/aero/aerodynamics.htm

I suspect psychological advantage of feeling “freshly shaven” has not been properly accounted for. Take a mannequin, stick it into wind tunnel, measure the force. Then tape some leg hairs, measure it again. I will be shocked (SHOCKED!) if the difference in drag is 7%. I bet it’s well below 1%.

Post a comment:

Comment sections can be a beautiful source of knowledge, conversation and comedy. They can also get pretty ugly, which is why we've updated our Comments Policy. If your comment isn't showing up or suddenly disappears, you might want to check it out.