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TECH FEATURES: RBA GOES AERO WITH BLUE COMPETITION CYCLES
Philip Booth
January 9, 2009
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Blue Competition Cycles first came on the scene in 2004 and has aggressively been making a name for itself on the racing circuit ever since. For 2009 Blue has taken aim at the high-end time trial and triathlon sector with their new Triad. The Triad features a monocque carbon frame that was developed in the wind tunnel to be one of the top performers on the market. The Triad’s aerodynamic features include aero tubing, internal cable routing, under the chain stay mounted rear brake and a 1” head tube to reduce frontal area. Along with aero features of the Triad, Blue is offering every costumer that purchases a Triad an hour of wind tunnel time at the A2 wind tunnel in Charlotte North Carolina.
 The 2009 Blue Triad
When the offer came from Blue for Road Bike Action to test a Triad and spend some in the wind tunnel, we packed our bags and headed across the country to Charlotte, North Carolina. The A2 Wind Tunnel outside Charlotte is a state of the art aerodynamic testing facility that features two wind tunnels. The larger tunnel is the only tunnel in existence that was specially designed and built for testing race cars. The tunnel is so well known that almost every NASCAR team uses it for aerodynamic testing and it is booked solid for the next two years. The smaller tunnel is used mainly for bicycles and specialty projects.
Mike Giraud crunches data from the wind tunnel
Mike Giraud runs the bicycle program at A2 and as we would quickly learn is an expert when comes to getting riders in their ideal aerodynamic position. Giraud has been in the bicycle industry for over fifteen years and has worked for high profile teams such as Rona, Timex and Saturn. Giraud has also helped setup a long list of top professionals including George Hincapie and Nathan O’Neal. The facility that Giraud and the A2 team have put together is impressive. Aside from the wind tunnel, they have virtually every aero wheel, helmet and handlebar setup for people to use while testing. Equally as impressive is Mike Giraud knowledge of each product, its performance and how each one effects airflow over the whole of the bike.
 The mounting platform rotates to simulate cross wind conditions
Once at the tunnel the first task was to set up the Blue Triad with my normal time trial position. Once the bike is set up it is mounted onto a platform in the center of the tunnel. The platform features two rollers that allow both wheels to spin and collects data. Once the bike is mounted it can be rotated at 5-degree intervals to test YAW or angle of the wind. This allows A2 to test rider positions and products in cross wind situations.
 Before entering the wind tunnel, information is collected about riding speed and distance
Before starting the test Giraud asks every rider a series of questions that includes what type of riding you do, the distances you are racing at and what speeds you are typical riding at during competition. All of these questions play a role in ones final position. For me, I will be doing time trials that range in distance from 20 to 40-kilometers, with my best 20K times hovering at about 26-minute mark.
The fans in the A2 wind tunnel can produce wind speeds up to 85-mph
Based on this information my position will be lower and more aggressive than a person doing a triathlon or and IronMan. Typically these positions are bit higher, to lessen the strain on the athletes back and to allow them use muscles similar to those that will use in the run portion of the event. The information also allows Giraud to figure out drag and watts differences at different speeds.
Once in the tunnel, there is a brief warm up period before the tunnel kicks on. The first run is a baseline run in the riders original position. The second run is again a baseline but with 5-degrees of YAW. Since my races are short the likely hood of prolonged crosswinds is minimal so we did not progress with 10-degree or 15-degree measurements. For IronMan or long distance riders Giraud will often take measurements out to 20-degrees.
Once the 5-degree measurement is taken the bike is reset at 0-degrees, and another baseline is taken. This is usually the measurement that Giraud uses as a baseline because he has found riders are usually overly tense during their first run.
Side View: Original Position
Front View: Original Position
With the baseline established, Giraud begins to make changes one at a time. Only one change at a time is made so that Giraud knows exactly what is affecting the numbers. There turned out to be two major problem areas with my position. While my back was pretty flat my head was sticking up from my torso and into the wind. The other area was that my elbow position was too far out. How high I held my head was surprising. I was aware of the issue with my elbows but have always struggle with bringing them in close without compressing my chest and restricting my breathing.
The first change Giraud made was to lower the bars 1-centimeter. This actually had little effect on my drag, but was comfortable and getting my back just a little bit flatter. Giraud then lowered my stem another centimeter. This position was still comfortable and we started to see a noticeable improvement. My drag dropped by .5-pounds and I saved 30-aero watts. Aero watts account for the number of watts saved through aerodynamics, but do not account for other factors such as rolling resistance and drivetrain friction. With my back lower it was time to address my elbows. Surprisingly the changes that Giraud made to my elbow position ended up fixing the issue of the way I held my head.
When we moved the armrest in closer we also moved them back toward the bike. This along with the lower stem repositioned my upper arms so that they were perpendicular to the ground instead of slightly out stretched. What this did was to allow my elbows to come together without compressing my chest. To get a feeling of the difference put your arms out in front of your body at 90-degrees, elbows bent with hands and elbows together. You will feel a little compression on your chest. Now if you keep your arms in that position but lift your arms so that your shoulder is at 100-degrees you will feel more compression in your chest as the chest muscles are pulled upwards. This moved lowered my drag by .23-pounds and saved 13-aero watts.
With my forearms now at 90-degrees, my arms were now supporting my upper body weight much more easily and I was able to relax my shoulders causing my head position to drop dramatically. The final change Giraud made was to again bring elbow in even closer together. This final change lowered my drag by .30-pounds and saved another 18-aero watts. With my new position finally dialed in, Giraud had me test several helmets to see which best fit my body profile. Both the Giro Advantage and yet to be released Specialized saved me an additional 2-aero watts.
 Side View: Final Position  Front View: Final Position
The final numbers were astonishing. After an hour in the wind tunnel I saw a14-percent reduction in drag over my original position, which approximately equates to a 1.5-mph increase in speed at the same power output. What was surprising is that my original time trial position was not terrible, but it was far from ideal for type of racing that I plan on doing.
The Blue wind tunnel program the only of its kind in the industry and is a huge step forward in helping consumers get the most out of their investment. Without purchasing a Blue Triad an hour in A2 tunnel costs $390. When considering the cost of a time trial specific bike, aero bars and aero wheels, the A2 tunnel could possibly be the best value in the industry when it comes to dollars spent versus increase in performance.
Look for a complete road test of the Blue Triad in an upcoming issue of Road Bike Action. For information on Blue Competition Cycles visit www.rideblue.com
For information on the A2 wind tunnel visit www.A2WT.com
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