Felt's Integrated Aero Triathlon Bike in Action!

When the triathlon was originally conceived in the late 1970’s, the cycling portion was a whopping 180 kilometres (112-mile) in length which required a great deal of strategising, not to mention an almost superhuman level of endurance.

Fortunately, as the triathlon event gained popularity, the cycling segment was shortened to a more modest 40 kilometres (25 miles), with the 180 kilometre effort left for what is now known as the Ironman Triathlon.

This quickly transformed the cycling component from a test of endurance to a more or less all-out sprint, which is why we now see a subtle but very important difference in the way that triathlon bikes are constructed compared to road bikes.

In this article we’re going to take a closer look at the main differences between a triathlon or “tri” bike, and a road bike, so that you can understand how their structures apply and are of benefit to your own training.

A Comparison of Road Bike Geometry Vs Tri Bike Geometry

1. Seat Tube Angle

The seat tube angle of a triathlon bikes allows for a far more aerodynamic position than that of a road bike.

On a road bike the seat tube is angled at around 73 degrees as a general convention, and the riding position is more upright. This ensures that the bike handles efficiently in a variety of riding circumstances, such as cornering and climbing.

On a tri bike, the seat tube is set at a steeper angle; usually around 77 degrees. This ensures that your hips remain open while riding.

The benefit of this open hip position is that your body will be positioned further forward and over the bike, increasing your aerodynamics and subsequently your speed.

Straight away the advantages of a triathlon bike over a standard road bike should be obvious, but there is far more to this than meets the eye!

Diagram showing the difference in road and triathlon geometries on a bike

2. Elbow Angle

The aerobars used on a triathlon bike enable you to rest your elbows on pads so that you don’t have to use the muscles of your arms and upper body quite so much to support the weight of your torso.

As well as helping you to feel more comfortable during the race so that you can focus on giving it your all, this aerodynamic style of handlebars places your elbow at a 90-degree angle to reduce strain and general wear and tear. With your elbow’s on a 90-degree angle, the body is supported by its skeletal structure, rather than using your muscles to stay upright. This saves precious energy during the ride, which can be conserved and used later in the race when it is needed.

To visualize how this can help your performance during a triathlon, think of the standard road bike position as a kind of push up, with the aerobar position being more like a half push up.

3. More on Aerobars

It should be noted that while aerobars are a great way of increasing the stability of your upper body while sparing your arms, simply installing a set of aerodynamic handlebars or elbow rests on your road bike could cause more harm than good.

The angle at which your thigh meets your torso will become lessened, meaning that there will be less distance between your leg and upper body at the top of each cycle or pedal stroke.

As your leg reaches the top of each stroke your body will be in a very cramped or closed position, causing a great deal of discomfort over the duration of the event while also preventing you from being able to exert as much force on the downward portion of your stroke.

It is also far more difficult to support yourself in a stable manner while riding in such a closed off position, and the larger distance between the saddle and handlebars compared to that of a triathlon bike will only serve to compound this further.

Tackling tight corners, grueling climbs, and generally stabilizing yourself on less-than-ideal terrain is going to be far easier with a combination of a triathlon bike and aerobars, enabling you to focus on your performance rather than having to worry about your balance.

A Rough Diagram of the positional difference in bikes

4. Muscle Recruitment

The overall geometry of a triathlon bike provides greater recruitment of the gluteus and hamstrings muscles during riding.

This is highly beneficial because it means that your quadriceps muscles will be less fatigued and therefore fresher for the running leg of the event.

When we look at these muscles while riding a road bike we see that they are placed in a position of greater flexion which, simply put, means that they are less able to contract.

Besides forcing the quadriceps to work harder, this can also place your lower back in a more vulnerable position, leading to greater discomfort and an increased potential for lower back pain which may prove fatal to your success when you come to transition from cycling to running.

It should also be noted that given the complex nature of a Triathlon Bike, ensuring that you get a proper fit to the bike at your local bike shop is absolutely critical.

A Bunch of Triathletes Mid Race

5. Which Bike is Right for Me?

Whether you choose a triathlon bike or a road bike is ultimately going to depend on a few different factors such as:

  • Your standard or default posture while riding;
  • If you intend to participate in a triathlon or Ironman event; and
  • If you want to simply ride with friends or enjoy long-distance cycling alone or with your family

In light of the evidence provided it should go without saying that participation in a triathlon means that you will definitely need to invest in a tri bike, not just for the event itself but for your training itself, if you wish to gain maximum results from the event.

If you use bullhorn handlebars and / or lean forward to a large extent while riding then a triathlon bike may be more suitable for you because its geometries lend themselves far more so to this style of riding.

Finally, if you want to race or ride casually without striving to achieve the absolute top speeds that you are capable of then a road bike is most likely going to be suitable for your needs and it will also be highly suitable for your day-to-day usage such as family outings.

The best thing that you can do before making your final purchase is to experiment and try out a few models of each type of bike so that you can make an educated decision based on what you feel works best for your body and your needs. If you are looking for a Triathlon Bike, the Felt B14 is a stunning-looking full Carbon Tri Bike for only $2,299, which you can view here.

I hope you enjoyed this post and found it useful. Leave a comment below and let us know about your experience with Triathlons and Tri Bikes - we would love to hear how you have found switching to a Triathlon Bike!