Case Study

Name: Jon Simkins
Age: 36
Lives: Banbury, Oxfordshire
Club: Banbury Star
Cycling: Competitive Time Trials ( 10 to 25 miles)

John’s briefing before the test:
"I have tried various positions over the last two seasons and become totally confused as to which position is the most efficient. Even If I only came away from this test knowing that my current position is optimum, it we be a good result because it would be great to stop chasing my position and get on with riding the bike".
"I am pleased with my performances this season, I regularly finish in the top five in Open Time trial events, usually about 20-30 seconds from the leader on  a 10 mile TT. I feel that my performance is starting to plateau now"

Test Results:
John used the DRAG 2 ZERO Elite package.  He tested 12 different combinations of position (15 test runs in total including repeats in his baseline position). This program took approximately 5 hours with 3 hours of actual tunnel testing.

Baseline position ‘A’.  
Drag Coefficient = X,  Power Output = Y

Intermediate position ‘B’. 
Drag Coefficient = X*0.949,  Power Output Y =1.01,  Comfort improved.

Extreme position ’C’.
Drag Coefficient =X *0.91,  Power Output Y*0.98, but position very uncomfortable and unsustainable.

The most extreme position ‘C’ shows a significant 9% reduction in drag. However, when ridden close to threshold there is a 2% loss in power and it’s clearly very uncomfortable.

Position ‘B’ actually gives a small improvement in power, which is a bonus given that there is a 5.1% reduction in drag. There are no issues with comfort, and this position is immediately useable without any additional training.

Recommendations:
The analytical model predicts the following for a given 10 mile TT course.
Position B gives a time reduction 26.4 seconds.
Position C gives a time reduction of 34.8 seconds.
John therefore adopts Position B for the remaining part of the 2007 season and then plans to work on aspects of Position C to improve power output and comfort for the 2008 season.

Feedback:
Since Jon’s recent wind tunnel session he has competed on the K10/10 (Princethorpe) and P613/10, improving his PB by 35secs and 37secs respectively. Many variables will of course have contributed to this result, such as weather conditions. More comprehensive testing is currently on going to provide correlation data for the Shrivenham wind tunnel and Drag2Zero protocol. Analysis of relative time differences to other competitors suggests that the change in riding position has contributed to at worst between 16 to 20 seconds of the total time gain. This correlates reasonably well with the predicted gains from the wind tunnel results for position B.

Andover
Andover P613/10 on 14/09/07 – Jon Simkins  19.37 3rd  Place ( Winner 19.02)
Andover P613/10 on 14/09/07 – Jon Simkins  20.16 14th Place ( Winner 19.17)

Princethorpe
Leamington C& CC K10/10 on 2/9/07 – Jon Simkins 1st ( 20.39)
Rugby Velo K10/10 on 9/6/07 – Jon Simkins 4th ( 21.14) – (Winner 20.21)