There are a number of factors that prevent you from going fast on the bike, but the two main characters are:
Frictional Drag- from the resistance between the air flow and the objects exposed to the air flow (their surface-area).  The resistance is a function of the viscosity of the air which, although very low, is significant enough to slow you down.
Pressure Drag-  from the eddying motions that are set up in the air behind the rider as they ride.  This is also termed wake (similar to that behind a boat).  This type of drag is a strong function of the cross-sectional area of the moving body (you).

The figure below is a good way of illustrating the two.  The object on the left is mainly subject to frictional drag, that on the right, pressure drag.

There are a number of equations associated with fluid flow but probably the most important is Bernoulli’s equation:

Why is this equation so important?  It relates the drag of a cyclist to his or her velocity.  You’ve probably heard that aerodynamics become more important the faster you go and it’s all due to the V2 term – drag is proportional to the square of your velocity  i.e.  Cyclist going at 10mph    V2  = 100      Cyclist going at 20mph V2 =400  i.e. 4 times more
As you go faster, your drag increases more so.

Below is a comparative list of the various modifications that you can make to your bike setup to improve drag – however, REMEMBER: The most aerodynamically inefficient part of cyclist is the rider themselves.  About 80% of the drag of a cyclist comes from the rider – bike FIT therefore is paramount since it affects aerodynamics on the bike and in particular, the pressure drag.

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Start-Tri plans on holding another ‘year-end’ PARTY event in conjunction with Paramount Adventure and a number of local sponsors.

The event will be in a similar format to last year.  Weather permitting we plan on running our ‘unofficial time-trial‘ course.  You can take a look at the course and practice on it beforehand.  We will be giving prizes for the fastest times.

We also plan on repeating the ‘bike-gear-swap’ – a great way to upgrade components for you existing bikes or even purchase a new bike altogether.

Last year we had Marty’s Reliable Cycle and Starting Line Sports stands providing new and sale gear also – we hope to have them back.

Where: Meyersville Grange (near the Meyersville circle) on Meyersville Road.

What to bring? Your self, kids, spouse, significant other…Old tri/running/biking/swimming gear for the swap meet.

STAY TUNED FOR MORE INFORMATION…

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Firstly, thanks to all who attended.

The weather was unpredictable but we managed to get cyclists off with the sun shining albeit on wet roads.  We changed the course a little from last year so the times are not directly comparable.  Also, the wet roads will obviously have affected the times a little.

Here are the results from those who braved the crazy weather:

Time-Trial Results

Congratulations to Lori and Arland for their great prize-winning times.

You will note that we’re opening this up to all and sundry – if you’d like to do the course and then email us your times, check out the time-trial page.

Many thanks to Lawrence Writer for helping out during the event.

Train and ride safe – Start-Tri.com

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Next week we plan on holding another unofficial time-trial through the swamp.

For those of you who did it last year, the course is similar although we won’t have it marked out so we recommend taking a look at the map.

If you’d like to sign up online, you can click the google checkout button at the bottom. Please print-out and sign the below waiver and bring along if you plan to participate.

When: Wednesday June 24, 2009 at 6:30 PM
What: The Time Trial (12.0 mi) will begin promptly at 6:30 PM with riders going off at timed intervals. The course will be available for pre-riding at your discretion. Course will NOT be marked with signs, nor closed to traffic. This is the course http://www.gmap-pedometer.com/?r=2884861 Riders must familiarize themselves with course ahead of time.
Where: Meyersville Circle (parking in convenience store lot, across from 223 HICKORY TAVERN ROAD GILLETTE, NJ 07933) or on street, Meyersville Road/Meyersville Grange/Public Ball field
Cost: $10.00. Prizes awarded to top male/female. Other prizes will be raffled.
Call 908-256-1738 or Email mickey@start-tri.com or Jason@start-tri.com

Name__________________________ M_____ F_____
Address_______________________________________
City______________________St___Zip_______
Phone # (___)__________________
E-mail Address ______________________________________________
Send to: 43 Bolton Blvd, Berkeley Hts, NJ 07922/Sign up on website at www.start-tri.com
Start-Tri.com, their leaders, officers, sponsors and/or anyone else connected with the training ride (Time Trial) shall not be liable for any injuries, illness, loss or damage to any person or property as a result in participation of this time trial. Each participant assumes the risk associated with a running event. I release any and all liability attributable in any legal way to the aforementioned groups. I attest to the best of my knowledge that I am physically fit and am able to compete in the time trial.

Please Sign (parent if under 18)____________________Date___________

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