Wes Hobsen continues uncovering the secret knowledge of improving your racing speed in triathlon.
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Speaker: Now the athletes are in my favorite segment, the bike segment and just as a wet suit can save time for a swimmer, so can he quicken it and save time for a cyclist through aerodynamics and to talk more about aerodynamics, let's go, talk with John Crawley down at the Olympic Training Center.
Lady speaker: Sounds good. Let's go.
John Crawley: What we have here is a very good example of a bicycle that has incorporated some of the newer aerodynamic features. You will notice right away that it looks a little bit different than a standard road geometry bicycle frame, with also some additional aerodynamic components installed.
What we see here first on the rear wheel is a rear disc wheel. You will notice that the open space of the rear wheel has been covered by this particular type of material. Basically, the design of this wheel is to essentially allow the airflow to go around the wheel instead of through it and cause a lot of turbulence with the spokes spinning very, very quickly. So this can add quite a bit of savings over a standard rear wheel just in the fact that the airflow coming off the back is relatively smooth as compared to a standard spoked wheel.
Coming a little bit forward, you can see that the tubing on the seat post and the seat tube as well as the tubing on the down tube has a very airfoil like shape to it. Two things that we are concerned about in terms of aerodynamics, one is the reduction of the surface area that is exposed to the wind as the rider is riding and secondly, is the drag characteristics of the material itself, both in terms of friction, shape, etcetera and so these two or these two examples of tubing, give you an idea that number one, we have reduced the cross-section of the tube itself. So looking into the wind, this frame sees less of the wind as a standard road frame geometry. Secondly, you will notice that the shape is very aerodynamic, much like the wing of an airplane. So the airflow is going to flow very smoothly around these surfaces thereby reducing drag and also improving the speed of the cyclist. You will also notice that on the seat tube, there is actually a cut out for the rear wheel. This is not only to give additional aerodynamic capability to this bike frame, but also, as we will talk about here in a minute, this is also a geometrical concern in terms of placing the rider on the bicycle. These chain stays have been reduced in length moving the rear wheel a little bit forward because the rider is going to incorporate a much more forward aerodynamic position. So we also want to maintain aerodynamic integrity, but not at the expense of rider's stability.
So as we come a little bit further forward, you can see here we have got some aerodynamic handle bars. These bars are designed to help the athlete get positioned in a more aerodynamic position much like a downhill ski racer would get into a tuck position coming down the mountain.
If you look further down on the front part of the bicycle, now you see that the fork has incorporated some of the aerodynamic characteristics that we have already talked about before. This is a bladed fork that reduces the amount of turbulence associated with the fork coming through the -- cutting through the wind. So therefore, this is another drag reducing device.
And lastly, the front wheel itself, you will notice it is a deep dish wheel. The spokes are bladed type or flat type spokes which again, create a lot less turbulence as the air passes through and around them.
Looking a little bit more at some of the other features that the rider can use, certainly, this helmet is, kind of takes two things into consideration. First thing is you will notice that the shape is a very soft contour shape and in fact, has a little bit of fairing at the back of the helmet itself, and this is designed to allow the airflow to come smoothly over the head and transition smoothly on to the back and away from the athlete. So it minimizes the amount of the turbulence or form drag that the rider will experience as a result of having this head gear on.
Secondly, you will notice there are some flow vents, strategically positioned around the helmet that allow for that -- some of that airflow to actually escape the helmet itself and come in and actually cool the athlete off a little bit.