Triathlon Bicycles – Do Slow Riders Save More Time?
Written by Fallan on April 4, 2009 – 2:39 am -Slow Riders improve more with Aero Equipment
Who benefits more from the use of Aerodynamic gear, a slow rider or a fast rider? For the sake of argument, let’s say that a slow rider rides a time trial at 18 mph or 30 kph and a fast rider rides at 25 mph or 40 kph.
Both riders have the same aerodymanic profile before and after implementing some aerodymamic peice of gear, let’s say, adding aerodymamic drop bars to their road bike frame. At this point, the physics of the riding can get a little complex, but the basic ideas are easy to follow.
As your speed on a bike increases, the amount of force you need to create in order to overcome the resistance provided by the air you ride against increases. With increasing speeds, come increasing forces. A faster rider spends more of her energy overcoming wind resistance than a slower rider.
The logical (but erronious) conclusion is that a faster rider would derive more benefit than a slower rider by implementing aerodymic measures such as drop bars, specialized tubing or helmet shapes, narrow arm profile, flattened back, etc.
So why, you ask, would a slower rider save more time than a faster rider with the use of aero gear?
Aha…that’s the key point is TIME savings.
Huh?
Think about it. In a race, the rider is concerned with not necessarily how fast she rides the course, but how long it takes to ride the course. Speed (miles per hour or kilometers per hour) is typically a secondary measure and is an afterthought when looking at finish line results. The overall time (hours, minutes and/or seconds) is what distinguishes first place from second plance and so forth.
I know what you’re thinking…
What in the world are you talking about Griffith?
In any given race, the bike leg is conducted over a fixed distance, say 20 k for an Sprint Distance Triathlon. The faster rider, going at 25 mph, is on the course for less time than the slower rider going at 18 mph. The first rider in this case would finish a 20K time trial in thirty minutes, whereas the slower cyclist finshes a 20k time trial in 40 minutes, a full 10 minutes later.
Now lets take both of those riders and give them some aero equiment, say switching from a standard road racing frame to a top end time trial or triathlon bike.
According to the math done by the folks at Cervelo, the speed gain by the faster cyclist is indeed more…a full 2 kph faster! And for the slower rider, the speed gain is significantly smaller, but still 1.4 kph faster. (These speed gains take into account the “speed squared” factor in calculating drag if you are doing the math at home.)
Revisit the 20k Time Trial Course
OK, now lets take these new speeds out onto our 20k Sprint Triathlon course.
The fast rider is now riding at 42 kph and the slow rider is riding at 31.4 kph…so who has a bigger time savings?
That’s right, it’s the slow gal that improves her time more…Over 20km, the fast rider finishes the bike leg in 28:34, a full 1:26 faster than her previous time. The slow rider is still slower, but finishes her leg in 38:13, a full 1:47 seconds faster!
The slower rider improved her time trial speed by 21 seconds more than the fast rider did!
If you’d like more detail about the math or figures used in this article, just stop on over to the Cervelo web site.
Tags: aero
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History of Triathlons – What is a Triathlon?
Written by Fallan on August 4, 2008 – 3:29 am -Triathlons are quickly becoming one of the most popular endeavors for athletes and non-athletes alike. Shows like MTV’s “Made” and NBC’s “The Biggest Loser” feature out of shape and overweight stars whose motivation for getting back in shape is to complete a triathlon.
Maybe you’ve been thinking of completing a triathlon as well and are wondering to yourself, “How Does a Triathlon Work?”
Triathlon gets its name from the combination of three sports. First conceived as the brainchild of Don Shanahan and Jack Johnstone a triathlon traditionally consists of swimming, biking and running. The first triathlon took place in San Diego, California as a “wierd event” to that was designed to even up the race field of runners…allowing people who were better swimmers and bikers (including the founders) to complete on a more even level with the pure runners in the Mission Bay track club. The group of friends designed a course that consisted of a 6 mile brun, 5 mile bike and 500 yards of swimming.
Four years later, two of the participants in the Mission Bay Triathlon organized the first triathlon in the now epinonymous town of Kona, Hawaii. While only about thirty participants completed that initial event at Mission Bay, thousands of people compete annually in the Kona Ironman Triathlon every year, not to mention countless races of all distances across the USA and around the world.
One of the most popular types of triathlon is a sprint triathlon which consists of a 400m swim (1/4 mile), a 10 mile bike and a 3 mile run. The exact distances vary from one venue to the next, but they are all within this neighborhood. If you are someone who exercises a few times a week in your sport, be it swimming, biking or running, you could probably complete a sprint triathlon without much (additional) training at all.
Not to say that you don’t NEED to train…by all means you should! The point is that there are triathlons for everyone from complete beginners to experienced endurance athletes. As athletes gain experience and confidence, they may want to proceed to longer distances, including the “Olympic Distance Triathlon” and the “Half Iron” Distance Triathlon.
When you are ready to get serious about triathlon training you may want to consider a Triathlon Bicycle which is optimized for the cycling portion of triathlon, helping you ride as fast as possible while keeping your legs fresh for the run at the end.
Source: Triathlon History
Got questions? Feel free to leave a comment about this post and I’ll get right back to you as soon as I can!
Tags: triathlon
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Zipp 808 Disc Wheeset
Written by Fallan on June 4, 2008 – 2:53 am -Zipp 808 Carbon Wheelset for Sale
UPDATE: Nov 11, 2008 – This auction has ended, but you can look for more Zipp 808 Disc Wheelsets for auction here.
Up for auction is this Zipp 808 Carbon tubular wheelset. Barely used originally from a Felt bicycle, and thus the graphics. The cassette body can use Shimano 8, 9 or 10 speed cassettes.
Comes with already professionally glued Conti Competition tubular tires. These wheels were ridden less than 200 miles and the tires less than 56 (first pair had a flat and were changed out). Wheels are perfect and straight. These are dimpled technology for golf ball faster times.
Reg. price is $2300 before tires and gluing! Get them cheaper now.
Professionally boxed, insured, and shipped to lower 48 for $26.00. Shipping limited to United States only please.
Click here for the Zipp 808 Carbon Wheelset Auction
The seller of this wheelset is Ultimate Bike, an eBay power seller with 100% positive reviews. Please direct all questions to the seller directly.
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Triathlon Bikes versus Road Bikes
Written by Fallan on May 4, 2008 – 2:46 am -What is the difference between road bikes and triathlon bikes?
To understand the difference between triathlon bikes and road bikes, it helps to understand the difference between road racing and triathlon racing.
In the majority of triathlons, the biking leg is an individual event. Each triathlete begins their bike leg when they finish the swimming portion of the race. As a result, racers are leavning the transition area with their bicycle every few seconds to minutes rather than racing as a large group. Each rider must depend only upon his or her own strengths to finish the bike leg as quickly as possible.
in contrast, when road racing, athletes use one another to strategically rest and attack througout the race, changing speeds frequently, even coasting through parts of the race. The varied speeds and body positions of road racing are simply not practical in triathlon bike racing, thus some of the equipment is slightly different.
Saving it for the run
Another major difference between triathlon racing and bicycle road or criterium racing is that the triathlon bicycling leg is follwed by a run of anywhere from 5 kilometers to a full marathon depending on the length of the triathlon. A triathlete must be able to conserve energy in the legs even while riding the bike in order to have enough strength and endurance left to complete the running portion of the race.
Road riders and racers on the other hand are able to “leave it all” on the road, working as hard as their legs can possibly work, without having to worry about another race leg ahead of them.
It’s all about energy conservation
In order to finish a triathlon race well, a triathlete must conserve as much energy as possible while still riding as fast and efficiently as they are able. If it sounds like a tricky balance, you’re right, it is. That is why training and equipment play such an important role in triathlon.
What makes a tri bike different?
THe key features that make a triathlon bike different than a road bike are:
Steeper seat tube angle and/or a forward seat post
A steeper seat tube angle, a “forward” seat post or both, position the riders hips further forward in comparison to the bottom bracket where the cranks are located. This shifts the emphasis from the major muscles used in the biking portion from the hamstrings to the quadriceps. By conserving energy in the quadriceps, more energy is available for the triathlete to participate in the run leg of the race.
Aero bars / bullhorns
Maintaining an aerodymanic position helps a triathlete spend the majority of the bike race riding at a steady state speed. While the lower position can result in more “twitchy” steering and handling, since the triathlete rides solo, rather than in a pack, there is more leeway for bike maneuvering without being concerned about running into another bike wheel and causing an accident.
Staying low in the aero drops also relieves pressure on the athletes hands and arms with the upper body weight supported by the skeleton…a nice comfort when arms may be tired from the swim.
Reduced Wind Drag
As bicycle speeds approach 18-20mp or more, reducing drag becomes a significant part of improving bike leg performance. Small design elements contribute to the “space age” look of triathlon and time trial bikes. Examples included contoured frame tubes with teardrop shaped cross sections, aerodynamic water bottles, water bottle cages stored behind the seat, rather than on the down tube and even frame “cut outs” allowing the rear wheel to take advantage of reduced drag by tucking in behind the seat tube.
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