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Super Bike Vs. Mid-Range Bike | GCN Tech Geek Edition

(electronic whoosh) – Hello and welcome to another GCN Tech Geek Edition video. A few months back, over on GCN, we released our cheap bike
versus superbike video. And it stirred up a whole load of debate. And having read the comments, we felt we definitely needed
to revisit the subject, but at a different price point. So we have done that, and we’ve picked a real milestone. 1,000 pounds, 1,000 euros, 1,000 dollars. It’s a super competitive
price point for bike brands. And therefore, if you buy one, you get a whole load
of bike for your money. Now to find out exactly
how much bike you get, you should go watch the
full video over on GCN. But right here, right now, I thought we’d take a closer look at our two bikes to actually really try an ascertain just what differences there are, and why that translates out on the road. (funk music) Firstly though, let’s deal with what is the same, starting with the groupsets. I mean, of course, not literally. The groupsets are vastly different. We’ve got Shimano Deores, and Shimano 105. And there are many, many reasons why they are different. But, I would like to draw your attention to one key similarity. And that is shifting performance. Or more specifically actually, the array and location of
the shifting ramps and pins that you find on the cassette, and on the chainrings. If you look closely, you will see that they are almost
identical in appearance. Meaning that, theoretically, you should expect similar levels of shifting performance, and drive-train efficiency between the two groupsets. And now of course, on the superbike, we have electronic Di2, meaning that actually, the shifting performance
is on another level. But while that’s half mechanical, the difference between the two will be much, much smaller. Now I put that to Shimano, and this is what they had to say. So, there we go then. What would make a
difference out on the road between these two groupsets? I think probably just the weight actually. Pure and simple. Now, what other similarities are there between the two bikes? Well I think the position
of the rider on the bike. Now bear with me, because clearly, when you take these bikes out of the box, they aren’t very, very different. But there is always that very
simple element of adjustment. You can almost guarantee
that you will be able to get your sandal in exactly the right position. And so therefore, when you are buying a bike, and you go to look at the
geometry charts online, the key things to look at are the stack and the reach measurements. Now when you compare these two bikes, you can see that our mid-range in Deores is 12 millimeters shorter, which is not a great deal, but it is 31 millimeters higher, which is pretty significant. And I will admit that with Matt’s super slam position on his Aeroad, it would actually be non-impossible to exactly replicate the position. The length is not a problem, simply swap out that 10 centimeter stem for an 11, or a 12, and you’ve got the reach totally sorted. But, even with a negative 17 stem on there, which is pretty extreme, that’s a minus six at the minute, you’d probably only be looking at losing about another 15 millimeters. Leaving you 15 millimeters too high on this bike. However, that is Matt’s position, it’s not mine. On my own Aeroad, I’ve got two centimeters of spaces underneath the stem, meaning that I could literally exactly replicate my position from my superbike over
onto that on Deores. And that’s pretty significant, because all the chat about bikes left to one side, fundamentally, the rider is the engine. And so if your position is correct, you’ll be able to get the same power out, and actually in terms of aerodynamics, you are also the biggest cause of drag. And so as long as your
position’s the same, you get the same
aerodynamic performance too. (funk music) So what about the differences then? Well, each and every component on our superbike is likely to be lighter than on our mid-range bike. And unfortunately, when you add that all together, that is quite a big difference. And it also makes it
quite a tricky problem when you try and upgrade a mid-range bike, because to actually save
any significant weight, would mean changing a number
of different components. And it’s a dilemma. And it’s not a cheap one. But the good news though, is that actually the
overall weight difference is not all that significant, certainly not when you compare it to body mass, for example. So our superbike is about 7.3 kilos. And our mid-range bike, is just over a kilo more. So what happens out on the road, then? Well, not all that much. It has to be said. I mean they definitely feel different. Lighter bikes respond differently, and that’s often attributed to the fact that they’ve got lighter wheels, and therefore have lower rotating weight. But it’s interesting, if you actually look into that, you’ll find it’s something of a myth. You actually couldn’t
measure the difference between heavy wheels and
light wheels out on the road. And even if you did
theoretical calculations, you’d see that it’s literally
just fractions of a second that separates the two in a like-for-like standing
start acceleration. I’d put money on the fact though, that you could feel that difference in a blind test. Perhaps one for another day. Now of course, it’s when you start to climb though that weight really becomes a factor. And if you play around
with an online calculator, like, you can actually predict just what effect changing
weight will have. So in this case here, this bike would be about 30 seconds faster outdoors at Tour De France speed, so six watts-per-kilo. And that would extrapolate out to a minute if your power-to-weight threshold was three watts-per-kilo. And that remember, is for just over a one
kilogram difference. Now inevitably, what these figures mean to you will depend very much on your perspective. Certainly I would guess it’s unlikely it would actually matter in the grand scheme of things. But just like with inertia, and the rolling weight, actually, I would suggest that you would be able
to feel the difference, even if blindfolded. And does feel matter? Well, yeah. It does to me. But it’s certainly not everything. A lighter bike does not necessarily make it more fun. Not by a long shot, in fact. (funk music) Then we have aerodynamics. Now this is a bit of a funny one, given that actually buying a superbike doesn’t necessarily make
it more aerodynamic. But we have made sure that we’ve chosen one that is. Because ultimately, if you want to go faster, it is of paramount importance. So what then is the difference between these two? Well it’s actually a subject deserving of a video in
its own right, probably. In fact, maybe even an entire series. But if we try and drill down, in essence, you’ve got drag, that can be separated into two things. You’ve got air pressure drag, and direct friction. So the former is when an object causes air to part from the surface of it as it moves through it. Now that creates a high-pressure zone in front of the object, and importantly, a low-pressure area behind the object, which is literally dragging it backwards. There is likely to be no significant difference between these two bikes with that latter friction drag. But what about pressure drag then? Well, if we look at the two bikes head-on, we see some pretty subtle, but nevertheless significant differences in the surface area of these two bikes. I mean for start, the Aeroad has a much
narrower profile head tube, and actually, so narrow that it requires special narrow profile
bearings made by ACROS. It’s also got a much
narrower handlebar on there, stem, and also forks as well. All of which reduce that high-pressure buildup in front of the object. And then, as we turn to look more towards the side and the back of the bike, we’ll see some even more
significant differences. Starting with the handlebars, a round tube has been replaced by that much lower profile, smoother shape. The difference is even more significant when you look at the frame tubes. So I’ve got a squared off profile on the mid-range bike. It’s been replaced by what’s called a Kamm tail design on our Aeroad. And so that mimics the aerodynamic properties of a tear drop, which is like the most
aero shape there is. But you chop off the tail, which is heavy, and also really quite complicated to make. But you still get the same properties, and actually the
aerodynamics improves even when you get around to
more of a crosswind. Now designing an aerodynamic frame set, is an incredibly time-consuming process. In excess of 10,000 frame designs will be modeled and then tested using computational fluid dynamics before the final few are probably printed out, and tested in a wind tunnel. Now that is expensive, but then so too, is the manufacturing process, whereby you take your
aerodynamic prototype, and then turn it into a suitably light, and stiff, and
comfortable frame set worthy of superbike status. And it’s also worth mentioning here, that it would be almost impossible to mimic these frame shapes using aluminum or steel. So that too adds considerably to the price tag. Because you have to make it out of carbon-fiber. Now there are things you can do of course to improve the aerodynamics
of your mid-range bike. Swapping out an Aeroad front wheel, and back wheel of course, but that will have less of an effect, will reduce your drag. And then actually, swapping out your handlebars
and stem for this one would supposedly save
you five and a half watts at 45K an hour. And even just timing out your gear cables at the front end will also save you probably fractions of a watt. Now this bike will never be as aerodynamic as this one, but you can close that gap. However, just like when we’re talking
about weight before you, it’s going to cost you. Because you have to do it piece by piece. Hopefully that has given you
a little bit more insight into the sides behind the results of our mid-range versus superbike video. It has I think, been difficult to quantify the differences between these two bikes. We do keep coming back to
that whole topic of feel. So what I think would be
absolutely fascinating next, is to see if we can concoct some kind of blind test, whereby the challenge
is to try and pick out superbike performance without knowing what
you’re actually riding. Watch this space, we’ll see if we can do it. Now in the meantime, if you fancy a little bit more nerdiness, why not check out or video
about the tire pressure. That is another Geek Edition. But until then, geek out.

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