Triathlon Bikes: What Is A Tri Bike, And Do you Need One For Your Triathlon?

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A triathlon is an endurance multisport race consisting of swimming, cycling, and running over various distances

But triathlon cycling has some key differences from most professional bicycle racing – not least in the form of purpose-built triathlon bikes.

A triathlon bike is a specialized bike designed for the unique demands of triathlons, including aggressive geometry, integrated handlebars, and aero bars to optimize speed and efficiency.

They often include features such as aero wheels, a steeper seat tube angle, and a more forward riding position to enhance the rider’s aerodynamics during the bike leg of a triathlon.

This article is your one-stop shop for all you need to know about tri bikes. We’ll be discussing:

  • What Is A Triathlon Bike? 
  • How Do Triathlon Bikes Differ From Time-Trial Bikes?
  • The Pros And Cons Of Tri Bikes
  • Do You Need A Triathlon Bike For Your Triathlon?

Ready to get into the nuts and bolts of triathlon bikes? 

Let’s go! 

What Is A Triathlon Bike: Title Image

What Is A Triathlon Bike? 

Triathlon bikes are designed specifically for use in triathlon races. They prioritize speed and aerodynamics above (almost) all other considerations.

At the original “Trois Sports” triathlon races of the 1920s onwards, competitors would use standard road bikes. This remained the case until the 1980s, when early iterations of triathlon bikes as we know them today started to make appear.

Richard Byrne is credited with developing the first triathlon bike design that incorporated a steep seat tube angle for improved aerodynamics. This set the foundation for modern tri-bikes, and since then manufacturers have evolved tri-bikes into what they are today. 

As well as being aerodynamic in themselves, triathlon bikes are also designed to allow the rider to assume a very aerodynamic riding position. They achieve this largely through the geometry of their frame and through the use of aero bars, which allow the rider to hunch themselves over the handlebars.

A triathlete in a green jersey rides a black triathlon bike on a road next to a lake.

How Do Triathlon Bikes Differ From Time-Trial Bikes?

Triathlon bikes are very similar to time-trial bikes, but with a few major differences.

The key contrast is that triathlon bikes factor in rider comfort as well as aerodynamics, whereas time-trial bikes favor speed at all costs.

This is down to the different uses of the two bikes. In a cycling time trial, the rider gets off the bike completely exhausted, having expended all their energy on the course. Once they reach the finish line, their job is done.

For a triathlete, they finish the bike ride and transition straight into the running phase, so need to have something left in the tank. The cycling phase of a triathlon can also be substantially longer than a typical time-trial, so comfort takes on more importance and must be factored into the bike’s design alongside outright speed.

One of the ways this dual focus is reflected in triathlon bike design is with a steeper seat tube angle than a time-trial bike, which allows the rider to push their hips forward on the ride and reduce strain on the hamstrings and engage the quadriceps more. This takes the strain away from some of the key muscles that will be needed for the running phase.

Triathlon bikes typically also feature small amounts of storage space for energy gels or basic repair tools and attachment points for a bidon, reflecting the emphasis on comfort and endurance in tandem with outright speed.

Finally, time-trial bikes are governed by strict rules from the UCI which dictate everything from bike geometry to tube shape. Though many major manufacturers model their triathlon bikes on their time-trial frames, tri bikes aren’t governed by the same rules.

Therefore, some triathlon bike designs can be much more experimental, and even the more conventional setups will often feature additional components that are illegal in UCI events.

The Pros And Cons Of Tri Bikes

The Pros

#1. Aerodynamic Riding Position

More than half of resistance and aerodynamic drag produced while cycling comes from the rider’s body. That’s why a frame design that enables the rider to assume a more aerodynamic riding position is such a crucial advantage. 

#2. Aero Bars 

Aero bars are handlebar extensions that mount close to the center of the handlebar and cantilever out over the front wheel. 

You’ll sometime hear these referred to as “triathlon aero bars” or “tri-bars”, but they all mean the same. 

By lowering the upper body and bringing your arms in-line with your torso, aero bars allow the rider to get into a far more aerodynamic position for faster speeds and lower wind resistance.

Aero bars are usually paired with bullhorn handlebars on a tri bike, enabling the rider to significantly reduce the fatigue and pressure on wrists and hands. 

Aero bars can be customized and adjusted to meet the right height and separation of the bars and arms for each individual riders’ preferences. 

#3. On-Bike Storage 

Many modern tri bike models have built-in storage solutions for holding basic tools for puncture repairs, as well as nutrition and hydration to keep you going throughout your competition. 

These storage features are built to be seamless with the bike design to avoid any resistance or reduction in aerodynamic efficiency. 

 #4. Aesthetic 

Last but not least… tri-bikes just look cool. They’re beautifully constructed bicycles that turn heads as you fly past pedestrians. 

Even if you’re just a hobbyist or honorary triathlon enthusiast – at least you can look the part!

A triathlete in a black jersey rides a black tri bike past a corn field.

The Cons

#1. Gears 

Most of the time, triathlon bikes come with groupset gears that prioritize flat roads. 

This is fine for most triathlons, but if your route includes some hills and steeper climbs – maybe consider some more varied gears for your tri bike. 

#2. Cockpit Layout 

Tri bike riders will be using the aero bars for most of the route, which makes accessing the brake levers more challenging.

This can be dangerous for competitive group rides or cycling on roads with traffic where quick breaking is a vital safety measure. 

#3. Versatility 

One of the setbacks with tri-bikes is their lack of versatility for different terrains, gradients and weather conditions. They’re typically slightly heavier than road bikes, which makes them less well-suited to climbing.

Given that they are designed for aerodynamics, adverse weather conditions and crosswinds can also present problems for triathlon cyclists. 

Strong winds can catch on the deep-section wheels and light frame to blow the bike around, which can make cycling that little bit more challenging – especially if you’re competing. 

#4. Comfort 

Although triathlon bikes pay more attention to rider comfort than time-trial bikes, the “aero tuck” position can still get pretty uncomfortable after a while.

Riding in the aero position is exposed – arms are forward, and your center of gravity is shifted away from the seat post towards the handlebar. As well as contributing to rider discomfort, this also makes reacting to unexpected events on the road more difficult. 

#5. Cost 

Triathlon bikes don’t come cheap!

Entry level bikes start from anywhere between $1500 to $2000, with elite models costing upwards of $10,000 (ouch). 

And that’s before buying new parts, clothing and general maintenance

That said, you’re paying for some of the most technically advanced bicycles on the planet. Inevitably this will cost you. But if you’re an interested in becoming a serious triathlete (and you have the disposable income) then it’s definitely something worth considering. 

A triathlete in a red jersey rides a triathlon bike at the head of a group as they cycle between cones leading. toa transition zone.

Do You Need A Triathlon Bike For Your Triathlon?

The short answer is no. You could certainly use a road bike for most triathlons as a beginner. 

But it’s worth asking yourself: How many triathlons are you planning on entering, and how competitive do you intend to be? 

If it’s just a one-off or you’re aiming to race at a casual pace, your bike doesn’t need to be expensive. The main thing is that your bike fits you correctly, and is safe and comfortable.


If this is the beginning of a newfound love for triathlons, or you’re aiming to compete towards the top of the field, it could be worth taking the plunge and investing in a triathlon bike.

In the long run, aerodynamic design and positioning will give you a speed and efficiency advantage you need for that competitive edge.

Found this article helpful? Learn more from the BikeTips experts below!

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Sonny is an avid biker and cycling writer based in London, United Kingdom. Though he loves road cycling, his true passion is shredding long-distance bikepacking and mountain biking routes on his custom Kona Dew Plus. In the city, Sonny commutes on his beloved fixie, a vintage track bike which he painstakingly rebuilt and repainted at home.

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