- If you're like me
then you want to be able to ride your bike faster,
so we've come to a wind tunnel
to test a load of common aero gains
to see exactly how much difference they can make.
Now, you can buy bling bikes and bling kit,
but that's expensive.
You can do it the old fashioned way and train more,
but that takes effort.
So before you do either of those things,
using science, we're gonna demonstrate a load of stuff
that'll hopefully make you faster, for free.
We're gonna be testing loads of cool stuff today.
Some things that you might not have even thought about,
but also things like clothing, numbers, and even beards.
Now to do this, we've come
to the Boardman Performance Centre
and we're gonna be testing with the help of
Dr. Xavier Disley from AeroCoach.
AeroCoach being a company that provides specialist
aero testing for pro-athletes
and also amateurs too.
(upbeat music)
Hi Xav, good to see you man.
- You too.
- Thanks for helping us today.
Chris has kindly volunteered
to do the riding in the wind tunnel.
- Guinea pig.
- Yep, but can you run us through the procedure
that we're gonna be doing to test the various things?
- So, what we're gonna do is we're gonna mount Chris
and his bike on the test rig.
And you can see the big turbine behind us.
What this is gonna do is it's gonna pull the air past Chris,
which is gonna be transferred
to the force plate underneath you
which allows us to measure the aerodynamic drag
that you're producing.
We're gonna be running you
at 45 kilometres an hour wind speed.
Now we use a slightly higher wind speed
just to make sure the data's as accurate as possible.
We can then convert that to wattage savings and time savings
at lower wind speeds afterwards.
- What this enables us to do is to present the data to you
at two speeds, 45 and 30 kilometres an hour.
And then you can simply choose the speed
that's most relevant to you and the riding that you do.
So, Chris what's, which one--
- Well, on a good commute, I can do 34 k's an hour.
So, I'm gonna use that.
- Cool.
The first thing we're doing is getting
a baseline measurement of Chris in a standard position
and then we can measure other things against that.
(upbeat music)
Now many beginner cyclists ride quite a lot on the hoods
and tend to not ride in the drops as much,
or in an aero hoods position.
So we're gonna test those different positions,
well, Chris is, and we're gonna see
how much difference they make
and how much time you can save.
(upbeat music)
We're gonna be presenting the results
from the wind tunnel testing in terms of watts saved.
So to put that into context,
if you save 10 watts at 30 kilometres an hour,
that's equivalent to a 0.8 kilometre per hour speed saving
and at 45 kilometres an hour, 10 watts is equivalent
to 0.4 kilometres per hour in speed.
- So, I mean, what we found was that,
just by moving your position around on the bike,
we got some really, really big improvements
in terms of your aerodynamic drag.
So if we take a 30 kilometres an hour speed,
dropping your position from a hoods position
down to an aero hoods position
was 33 and a half watts faster,
which is absolutely loads.
- That is loads, isn't it?
- That is quite a lot, yeah.
So what's my CDA then?
I love that number.
- So your CDA was 0.221,
which is actually a pretty good CDA for someone on a TT bike
so it was quite an extreme position you were holding,
so I'm not surprised that it was that low.
- It's the sort of position you'd only hold from a lead out,
you know, two or three kilometres at a time
when you're really, really going for it.
- Exactly.
We found that when you went into the drops,
it wasn't quite as fast.
We often find that.
That an aero hoods position,
because your forearm is parallel to the airflow,
when you go down to the drops,
more of your forearm is exposed to the air,
so it's a little bit slower,
but it can be more maintainable.
'Cause going in an aero hoods position
can hurt your triceps a little bit.
- Yeah, it takes the pressure off.
- Exactly.
- I guess the takeout message would be
whenever you're going fastest in an event or on a ride,
the most efficient position to therefore get into
at that point in time,
if you can only maintain it for a short period,
is that aero hoods position.
- Absolutely, absolutely.
And when we were in the tops,
so rather than hoods position, when you're holding the tops,
it was a little bit slower.
Your elbows went out a little bit
and it was about three watts slower
at 30 kilometres an hour.
And it's a lot related to torso angle,
so the lower you get your torso angle, in general,
the faster you go.
Certainly on a road bike.
- So that really is the big take home,
is to close that front cavity that we create.
- Yeah, exactly,
Allow the wind to go over the top of your back,
rather than hitting your chest instead.
- That's something we can all do at home quite easily,
isn't it?
For free.
- Yeah, it's just training
and making sure you can maintain those, kind of,
more extreme positions.
But even if you just, as you say,
hold the position occasionally,
it's still gonna speed you up.
You don't have to do it the whole time.
(upbeat music)
- Rain capes are great for keeping you dry
when it's raining,
but what is the aerodynamic penalty of wearing one?
They're a lot more loose and flappy
than a tight-fitting jersey,
and also many riders tend to keep a rain cape on,
just to keep themselves warm,
even after it's stopped raining.
So we're gonna see what penalty comes with that.
Also we're gonna partially unzip the rain cape
and see what happens if it turns into a parachute
and also fully unzip it
and leave it flapping around in the wind,
because many riders rather than completely taking it off,
they don't wanna stop
and they can't take it off on the move,
so they just kind of leave it on,
but unzip it so they don't get too hot.
Chris has just unzipped his rain cape halfway
and you can see that that's causing all the air to come in
and inflate it like a sort of parachute
and, well, it doesn't look very aero,
but I can't wait to see what the data says.
- And we found that putting a rain cape on slowed you down.
Not surprisingly because it is a bit more baggy
and it was 13 watts slower to put the rain cape on,
rather than just having your normal jersey.
When you half unzipped it,
that actually was interesting.
It actually wasn't any slower
and it looked a little bit quicker
when you half unzipped it.
Aerodynamics is a funny thing
and sometimes that sort of thing happens,
but there was a bout 3 watts in that,
when you unzipped it.
It was still slower than not having the cape on, of course.
- That's incredible 'cause I would instinctively ride
with it zipped up because I would be fearful of it
slowing me down.
- Normally that's what we'd see as well,
so maybe related to the position you were holding
and the particular jacket that you had,
but we certainly found that when you fully unzipped it,
and it was flapping around everywhere,
that was 16 watts slower than having it fully zipped up
and 29 watts slower than not having it on at all.
- And I should point out,
16 watts doesn't sound like a lot,
but when I sat on the bike
in the wind tunnel at 45 kilometres an hour,
you can feel it blowing you back.
The extra drag over having just a short sleeve jersey on.
- So what happened when Chris took the rain cape off
and stuffed it up the back of his jersey?
Was he faster or slower or--
- It didn't really make much difference.
It looked actually about one watt faster,
so not really that much difference at 30 kilometres an hour
by putting it up the back of the jersey.
- So that's not much difference on
not wearing a rain cape?
- Exactly.
Yeah, not the rain cape itself.
So once you don't need the rain cape anymore,
stick it up the back of your jersey,
or down, you know, one of the pockets,
if you can fit it in there,
and that'll definitely be much, much faster
than keeping it on,
because, you know, it's about 12 watt difference.
- Even at a modest 30 kilometres.
(upbeat music)
- I have the inability to grow a beard,
but thanks to Ollie's bag of tricks,
we do have a costume beard that I'm gonna wear.
See if it's any faster or slower.
- Right, so we're gonna test Chris with a beard now.
I don't know if this'll be faster, slower, the same.
I just really wanna find out
if having a massive beard on your face--
- I'm just worried about how I look, Ollie.
- You look great man, I'm gonna take a picture.
- That's all that matters.
(upbeat music)
A beard is faster.
- Aerodynamics is a funny old thing.
- Wow.
- So next up, well we have the beard.
I mean everyone wants to know is a beard faster or slower?
- Now beards are gonna be very individual
and depending on the position you're holding and things.
We've done, you know, some testing with people with beards
and we know that having a beard doesn't necessarily
make the rider massively slow.
Interestingly, with you, with your luscious beard
that you had on today,
it was actually a little bit quicker.
- Oh, wow.
Yeah I know, so but that was in the hoods position.
I wonder if it might be different if you were in the drops
or in the aero hoods position.
- So if I want to go for a ride on the hoods
I should grow a beard.
- Yeah, I think so.
- Right, there we go.
- That was saying it was, what, four watts quicker?
- At 45 kilometres an hour, yeah.
- I mean, how accurate is that?
Should Chris really be getting some kind of beard graft now?
'Cause he can't grow a beard.
- I think--
(laughing)
I think the problem is at 45 kilometres an hour
you're not gonna be doing that sat up like this.
And so, I'd wanna do more testing with him
in a bit more of an aero position.
But it filled the gap nicely around your chin.
- Nice, yep.
Kept my neck warm.
- Yeah, exactly.
- So you think a good thick thatch is the way to go,
rather than a wispy--
- Yeah, I think so.
I think that'd be more aero.
You could gel it down to make it more sleek as well.
- I think more testing is required on the front of beards.
(upbeat music)
The next thing we're gonna test is the effect
of sticking a cardboard number to the front of your bike.
Now, many of us have to do this if we do a sportive
or another such event for the purposes of timing
and things like that,
but what is the aerodynamic effect of this?
Is it faster, is it slower?
If you've got a fancy aero bike, or a handle bar,
does it completely ruin the aerodynamics?
We're gonna find out.
- It's ruined the style of my bike, Ollie.
That's for sure.
- Yeah, it doesn't look great.
So, I'm just sticking the number now
in a more aerodynamic way,
by folding it around the head tube of the bike
to see if this results in a significant saving.
- It does look better I'll give you that.
(upbeat music)
- Next up we're gonna test a race number
and how much it slows you down, if at all.
But, we're gonna test it twice.
We're gonna test it first well pinned
and nice and flat.
And then we're gonna test it
not so well pinned on
and kind of flapping around
and seeing if that makes a difference.
- If this is your idea of a well pinned number on here.
- (laughing)
- I'm a little bit worried.
- Wait, hang on, no I'm gonna,
I'm rectifying it, I'm rectifying it.
Apparently they weren't happy with the proficiency
of my number pinning,
so Xavier is insisting on pinning the number on
the AeroCoach way, whatever that means.
- A little fin, as in like a spine on the number?
- Yeah.
- And finally, we'll look at the effect
of badly pinning a number.
It's a kind of common held myth among cyclists
that it can really slow you down if you
pin your number on like a noob.
But let's see if it's actually true.
Then we went for the numbers, right.
So first up, yeah, the number, the sportive number
on the front of the bike.
- Now that's always gonna be a really tricky one
for people doing sportives
because you have to have a number on your bike
and so you need to know the best way to place it one there.
Having the big square number right on the front of the bike
obviously was slower,
but in this case it was absolutely loads slower
and at 30 kilometres an hour, it was costing
around eight watts, eight and a half watts.
- That's at 30?
- At 30 kilometres an hour, yeah.
- That's, I mean that's basically,
well, if you've got a fancy aero cock pit on your bike,
that's completely cancelled out the benefit
of that aero cock pit, hasn't it?
- Absolutely.
If you think about the frontal area of the number like that,
it's way more than the head tube of the bike,
or most of the handle bar as well,
'cause it's, you know, quite a big surface area.
So, I'm not surprised at that,
but hopefully it'll highlight to people
that maybe placing a number in a better position
is gonna be a better thing to do.
And the next thing that we did--
- Yeah, my hack, my cheeky hack
of wrapping it around the head tube.
Is that faster or slower?
- So wrapping around the head tube,
actually was pretty much no difference
to having nothing on the bike at all.
Maybe marginally faster, because--
- Faster?
- Yeah, because it helps to aero off
the back of the head tube,
but certainly it's much, much better
than having the number just front on to the airflow.
- You should leave your number on after a sportive,
because it is faster,
only if you've wrapped it.
- Only if you've wrapped it around the head tube, yeah.
- The next things we did were pinning numbers
on the back of the bike, on the back of the rider.
And we found that having just a pinned number
with a few pins on the back
was a little bit slower,
about half a watt slower,
which is what we'd expect.
Now, this was in a hoods position
when you were quite upright.
I think that if you were more crouched over the bike
there'd be more airflow going over your back
and then the influence of having a number
would be a bit more exaggerated.
So that half a watt might double, or maybe treble
to a watt and a half.
We did a little trick, a little AeroCoach hack,
where we pulled the edge of the number in,
to create a little fin off the back
and that actually sped you up by a watt and a half.
- Oh, wow.
- It's something that we've done for a while
and yeah, it basically extends the attachment
of the airflow off your back.
- So a pinned number, that's done well, is faster.
- Can be faster, yeah.
- I never knew that before today, that's pretty cool.
- And then, unpinning the number,
actually in your case simulated
that little hack that we did.
So, having two pins at the very top of the number
and then the back of it flapping
was a little bit quicker than nothing at all,
because it looked like that little fin at the back.
But I think if you'd unpinned the top of the number
and it'd been flapping from the top down,
it would be loads slower and that's what we needed to see.
- Well, thanks, Xav.
That's been fascinating.
So much like cool stuff we've learned today.
I hope you found this video useful and informative.
And if you've got any mates that have big beards
or ride with their rain capes unzipped,
then share this video with them and tag them in it.
And if you'd like to watch another video
with some aero testing in a wind tunnel,
then click on Xav.