Can one bike do it all?

I really like talking about the bike portion of triathlon for two main reasons. First, I really enjoy biking. When I did the Boulder Sprint last weekend I gave up a chance to do the Elephant Rock Gran Fondo which is a lot of fun and I was disappointed. Secondly, the technical nature of the bike is something that appeals to me. We aren’t just working out, we are operating a machine with nuts and bolds and sprockets and pieces etc. All of those come to together (along with the athlete) to produce an athletic result.

I have talked before about tri bikes vs road bikes and I have talked about how Sarah and I got fitted on the tri-position on our road bikes. I like to draw this contrast because even though a tri or TT bike looks so much different than a road bike, a lot of those differences are of questionable value to the average triathlete. This brings up the question then, can one high quality bike do both triathlon and a Gran Fondo like Elephant Rock?

Lets start with a comparison of sorts between two riders at last weeks sprint with a focus on body position relative to the wind. I focus on this because the human body is the largest aerodynamic drag on the bike, by a wide margin. Getting the body into a more aerodynamic position is the most critical aspect of an effective TT/triathlon position.

Kaira on Q-Roo Sarah aero

The rider on the left is Kaira, a friend of ours and fellow triathlete, who is riding the Quintana Roo Kilo. On the right is Sarah, on a Trek Doman 5.2 modified with a pair of tri bars and a Retul fit from Colorado Multisport. We are looking for an aerodynamic body position, that is, how low can you get into the wind. From these pictures, which are not the best, you can see they are very similar, but Kaira appears to have a slight advantage. Sarah looks like she is riding a little taller on the bike, but not that much taller.

Other than the seat position the Q-Roo has an aero bike frame and an aero seat-post. Neither bike has race wheels and neither rider is wearing an aero helmet. On the topic of the seat post, a lot of things mentioned right below the aero cockpit when you read an advertisement for a Tri bike is the seat post angle. It is said that the tri angle helps “save your legs” for the run. Maybe this is true but for comparisons sake it is worth pointing out that the Trek seat post was adjusted in such a way to simulate a Tri seat post.

Looking closely at the pictures you notice that the riders’ knees are coming close to their elbows and handlebars but not too much so that comfort is compromised. The Q-Roo Kilo is known for its comfort in this regard. When you compare these two bikes, both can do triathlon. The Kilo can do a Gran Fondo because if Kaira has to get on the “horns” when being in aero is illegal (as it is in many group rides if you are within a couple of meters of other cyclists) her comfort will be OK. For Sarah, she can just take off the tri bars and go back to her road fit for the Gran Fondo, or keep them on depending on preference.

From the softer end of triathlon bikes, the difference between them and road bikes with aero bars is fairly minimal and as a result either bike can competently wear either hat. Either bike can be specced up with race wheels for serious racing. The Trek obviously can’t change it’s bike frame or seat post design but (as we will discuss in a later post), those two things are surprisingly less important than one would think. In fact, an aero seat post gives you about as much aero gain as holding your pinky finger out has in drag gain. That is to say, there is not much advantage to an aero seat post!

Now, for fun, lets look at the top end of road and tri bikes. Since engineers know that the human body is the biggest drag creator, they get extreme. Lets look at Fabian Cancellera, the famous Swiss time trialist, on his Trek Speed Concept.


His body is a good bit lower than Kaira or Sarah. His legs could probably smack his elbows. The top tube is so short that his elbows rest at a 90 degree angle when in the aero position. It is nearly impossible to duplicate this on a road bike because even the top end Trek Madone can’t get a rider into that position. Sure, you can drop the body lower and raise the seat but the top tube is too long, the rider would be crunched down too much and you wouldn’t get a good position on the aero bars. The fit on the top end Madone or Domane would look similar to the mid-range Madone or Domane. However, the top end Speed Concept is much more aggressive than the Q-Roo Kilo.

Time trialing is a little different than triathlon and the fit is a little different. Lets look at an ironman on a Speed Concept. Trek Speed Concept

The body position is similar, and from this angle you really get a sense of how far forward the body is on the handlebars. His elbows aren’t as perfectly angled as Fabian’s, this is either by design or, since Fabian is a Trek sponsored athlete, he got a more perfect fit.

Obviously the Trek Speed Concept works great as a Triathlon or TT bike but would you take it on a Gran Fondo? Well, you could, but you wouldn’t. Primarily because in a GF it is against the rules to ride in aero around other riders – if it is allowed at all. If you are in a competitive GF, the officials will penalize you for breaking that rule, it is a safety issue. Riding a bike that is that aggressive on the horns is inefficient aerodynamically and, as people have told me, not comfortable at all.

At the top end of the TT/Triathlon scale, road bikes can’t compete. Similarly, top end road bikes are really no better (maybe even worse) with aero bars than mid-tier road bikes with aero bars. Top end road bikes are clearly more appropriate for a GF or really any time a hill needs to be climbed. As the bikes get more expensive, they actually get less flexible. There is actually a point at which buying more actually gets you less bike. In economics this is called the point of diminishing returns. The more you put in, the less you get out.

Let us also not forget that the most important part of the bike is they guy or gal riding it. Fabian on my bike will destroy 99% of the field of any triathlon on the bike leg no matter what the field is riding. The most efficient and cost effective way to gain speed is to improve the rider. 


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