Aero Bars Vs Drops – Which Is Fastest? | GCN Does Science

Aero Bars Vs Drops – Which Is Fastest? | GCN Does Science


(frenzied music) – Time trials are a great way
to try your hand at racing. They’re relatively inexpensive, there’s lots of local events,
they don’t take very long, and, if you’re new to
cycling, there isn’t that intimidating pressure
of riding in a peloton. But when I speak to people about having a go at a time trial, they’re often worried about the kit. They say, “do I have a time trail bike?” Well, the thing is,
you don’t actually need a time trial bike to do a time trial. I mean, yes, if you
want to be competitive, you probably do need a
fancy, time trial bike and all the gear. But, if you just want to see
how you go in a time trial, or maybe measure your
improvement week-to-week as you get fitter, all
you need is a road bike. (frenetic music) Now, one piece of kit that’s a really good value-investment for the occasional time trial is a set of clip-on aero bars like these. They’re great for entry-level
time trials or triathlon. Now, because I love time-trialing, and I wanted to ride my
bike fast if I could, I thought I’d do a
little experiment to see how much quicker, or not,
these clip-on aero bars are than just riding on the drops. In terms of experimental setup, I have my Orbea Orca Aero road bike with deep section, Vision
wheels, and a power meter. Now, set up a test time trial course, two kilometers long,
on a slight uphill drag through Corvara and Alta Badia. “Why uphill,” you might ask. Well, the reason for
choosing an uphill drag is to help hold a consistent power for the whole test course. I’m gonna ride it three
times in each setup. Now, the reason for doing
three tests with each setup is that an average of several tests will give us a more reliable result. And also, if any result
is obviously anomalous, we can discount it, and repeat. So, when it comes to swapping
the aero bars off the bike, I wanted to keep the total weight of the entire bike the
same, so that the only thing that we’re changing is
the position on the bars. So what I’ve done is I’ve
weighed the aero bars. And they’ve come in at 280 grams. And for the run without the bars, I’ve gotta bottle with
280 milliliters of water. And for the run with the aero bars, I’ve got an empty bottle. So the weight difference in water makes up for the weight difference
in the clip-on aero bars. I’m gonna do a rolling start
at 30 kilometers an hour. (dramatic music) (heavy breathing) Right, about to set off on
run two with the aero bars. I’m gonna have a rolling start
at 30 kilometers an hour. Let’s go. (active music) Right … run three, with
the aero bars: here we go. (resolute music) Right, about to set off on the first run without the aero bars. I’m gonna ride on the drops. So, I’ll set off now
and do a rolling start at 30 kilometers an hour. (robust music) Right, run two, on the drops. (powerful music) Right, run number three,
on the drops: here we go. (pulsing music) Well, the results are in,
and I’m surprised to say there’s actually quite a major difference. There wasn’t actually expected
to be a huge difference over only two kilometers. But, without the aero bars,
I averaged 1.3 watts more. And yet, I was an average
of 15 seconds slower over the two kilometers. If you multiply that by 20,
to get a 25-mile time trial, which is 40 kilometers, that adds up to about five minutes of difference. That’s a lot. That is a big difference. (commanding music) The reason I’m surprised by this result is that I know that the
most important thing for aero gains and aero
losses is your frontal area. And, for most people, that
means that to go faster, they need to get lower at the front. Now, on this aero bike, I
can’t actually get super-low at the front, because I’m a bit short. So, when I put the aero bars
on, I don’t get any lower. In fact, if anything, I
got a little bit higher. And I thought that would mean
I might actually be slower with the clip-on aero bars. So, how did I get quicker? Well I think, what it might
be, is that with the aero bars, my elbows were closer together. So my arms are narrow. Whereas on the drops, arms are out here, and I was wider. So that might be where
the gains came from. Either way, it’s fascinating. It shows that you can actually
make quite a big difference with just a simple piece of kit, like some clip-on aero bars. Another major advantage of aero bars which we didn’t test here is that, often, people find that they can relax better on aero bars than on the drops. Because you need fewer
muscles in your back and shoulders and arms to
hold yourself in position. And if you’re using your
upper-body muscles less, that means you’ve got more energy for your legs to push hard. (confident music) Hopefully, this video
will whet your appetite for time-trialing, and show that if you fancy having a dabble, the equipment should
really not be a barrier. But it also shows that
remarkably small adjustments can make a big improvement in your time. If you’d like to watch
another video about this, why not check out why size is
important in flat time trials at least by clicking down here. Or, you can check out the
Geek Edition of this video, where we look at the
nitty-gritty of aerodynamics by clicking down here.