When it comes to triathlons, the question of whether to use a road bike or a triathlon time trial (TT) bike is a common one among triathletes.
Both types of bikes have their own unique advantages and disadvantages, and the best choice ultimately depends on your specific needs and preferences.
Here we will discuss the differences between a road bike and triathlon TT bike plus clip on tri bars and their relative merits and which one is best for your big race this year.
Contents
- Differences between a triathlon bike and a road bike
- The Middle Ground – Retro Fit Tri-Bars on Road Bikes
- Why are there specific bikes for triathlons?
- Triathlons Went from Endurance to Speed
- Bicycles for Cyclists
- Bicycles for Triathletes
- Which bike is better for a triathlete?
- Conclusion – What Bike is Best for You?
- Frequently Asked Questions
Differences between a triathlon bike and a road bike
Road Bike
A road bike is a traditional bicycle design that is built for speed and efficiency on paved roads. They typically have a lightweight frame, narrow tires, and drop handlebars that allow you to switch between multiple hand positions. Road bikes are great for long-distance riding and can be used for both training and racing and even commuting. They are also versatile and can be used for other types of cycling, such as touring or recreational riding.
The major difference between the triathlon bike and the traditional road bike lies in the geometry of the bicycle frame. Specifically, the seat tube angle. The seat tube is the long tube extending from the bottom bracket upward towards the seat. And the angle of this tube relative to a horizontal line drawn at the bottom bracket represents your seat tube angle (take a look at the diagram below).

What does this mean for you? It means you will be more upright when riding and more often than not more comfortable. But you will be less aerodynamic.
The main characteristics of a road bicycle include:
- Lightweight frame: Road bikes are designed to be lightweight and efficient, with frames made from materials such as carbon fiber, aluminum, or titanium.
- Narrow tires: These tires are designed for speed and efficiency on paved roads, with a smooth tread pattern and a high-pressure rating.
- Drop handlebars: These handlebars allow the rider to switch between multiple hand positions, including the traditional “drops” position that allows for better aerodynamics.
- Gear ratios: Road bikes have a wide range of gears, allowing the rider to tackle a variety of terrain and gradients.
- Multiple water bottle cage mounts: Road bikes have typically two water bottle cage mounts, which allows the rider to carry enough water to stay hydrated during long rides.
- High-performance brakes: Road bikes typically have high-performance brakes, such as caliper brakes or disc brakes, which provide more stopping power and better control.
It’s important to note that these characteristics make road bikes more versatile than TT bikes, and more suitable for long distance comfortable riding, touring, and recreational riding, as well as for road racing.
Triathlon or TT Bike
On the other hand, a triathlon TT bike is specifically designed for triathlons, with an emphasis on speed and aerodynamics. These bikes have a more aggressive geometry, which puts you in a more forward-leaning position, and feature aero bars, which allow you to rest your forearms on the bike and reduce wind resistance. They also have a more aerodynamic frame design, which helps to minimize drag and increase speed.
For a triathlon bike, the seat tube angle is typically 76-78 degrees. A good bit steeper than the 72-degree angle found on most traditional road bikes. The steeper angle places the rider further forward on the bike creating a more aerodynamic body position. (See diagram below)

The main characteristics of a triathlon time trial (TT) bike include:
- Aerodynamic design: TT bikes are designed to minimize wind resistance and increase speed, with a smooth, aerodynamic frame shape and minimal ventilation.
- Aggressive geometry: The riding position on a TT bike is more forward-leaning than on a traditional road bike, which allows you to be more aerodynamic and reduce wind resistance.
- Aero bars: These are handlebars that extend out from the base bar, allowing you to rest their forearms on the bike and reduce wind resistance.
- Integrated braking and shifting systems: These systems are designed to minimize drag and increase aerodynamics.
- Deep-section wheels: These wheels are designed to reduce wind resistance and increase speed.
- Fewer or no water bottle cages: As the rider is in a more forward-leaning position, it can be harder to reach the water bottle, so some TT bikes don’t have water bottle cages, or have them in a different position. This is an important consideration if you are going to race a longer event like an IRONMAN event and worth investigating the options on the bike you choose. Here’s an example of a triathlon TT bike hydration system from XLAB.
The Middle Ground – Retro Fit Tri-Bars on Road Bikes
There is a middle ground, and you can fit tri-bars on to a standard road bike to make you more aerodynamic and shave time on the bike leg.
After installing aero bars, riders typically find that they’re going 1 to 2 mph faster at the same level of effort. Over a distance and time, this equates to about 1min 40s per 40km faster than without aero bars.
Aero bars, sometimes called “clip on aerobars”, “triathlon aero bars” or “tri-bars”, are handlebar extensions that mount close to the center of the handlebar and cantilever out over the front wheel.
The key is to fit the right ones for you and your bike geometry, and this should involve a bike fit to get you into the best and most comfortable position. As mentioned earlier the geometry of a road bike is different from a triathlon TT bike so this will be a compromise but can save you money over buying a triathlon bike.
Why are there specific bikes for triathlons?
When the sport of triathlon was created in Hawaii back in 1978, otherwise known as the Ironman®, the 112 mile cycling portion of that race took on the flavor of a traditional “road race” performed during most cycling events. The “road race” is typically a longer Point A to Point B bike race requiring both endurance and strategy.
Speed usually takes a back seat until the latter part of the race. And the most famous event of this type is the Tour de France. A three week bike race almost entirely made up of daily “road races” covering over 100 miles per ride.
However, as the sport of triathlon began to draw more participants, not everyone wanted to or could handle the distances covered in an Iron distance event – 2.3 mile swim, 112 mile bike and 26 mile run.
Triathlons Went from Endurance to Speed
So in order to make this sport more appealing to the masses, the distance of the triathlon was shortened. For the cycling portion of the triathlon, this meant shortening the distance from 112 miles to 25 miles. No longer was endurance and strategy a major component of the bike ride. The new objective of the tri-cyclist was to get from point A to point B as fast as possible.
The cycle leg had taken on an entirely new personality resembling the traditional “time trial” also held during cycling events. But the increase in speed brought about a new dilemma for the triathlete: How to overcome leg fatigue in preparing for the run after a 25-mile bicycle sprint.
Bicycles for Cyclists
Typically, a cyclist competing in a “time trial” will perform the event aboard a road bike with the standard 72-degree seat tube angle. This angle places the rider in a position on the bike so that he or she can utilize the major muscle groups of the legs – the quadriceps and the hamstrings. And when using these muscles to their fullest extent, the cyclist can achieve maximum output or power with the result yielding speeds in excess of 30 mph.
Not bad huh?
But…
The cyclist, at the completion of the “time trial”, will climb off the bike and REST.
Bicycles for Triathletes
Not so for the triathlete.
A triathlete has to hop off the bike, strip off their bike helmet, pull on some running shoes and take off on a run at any number of distances depending upon the race. And the speed at which the muscles acclimate to running legs from cycling legs is critical to the outcome of the overall triathlon performance.
By the mid-to-late 80’s, triathletes at all levels struggled to find a solution to this problem. I remember viewing a videotape of the infamous 1988 stand off between Mike Pigg and Mark Allen during the National Championships held on Hilton Head Island. During the cycling leg of the race, I notice something very unusual and relatively radical at the time. While riding his traditional road frame Pigg was sitting on the forward tip of his saddle…OUCH!
But why?
The theory was (and still is), that by riding at a more forward position, not only are you are more aerodynamic on the bike, but you are also putting less emphasis on your quadriceps muscles. Thus saving your legs for the run portion of the triathlon.
Bicycle pioneers such as Dave Empfield of Quintana Roo believed in this theory and sought to create a product to satisfy the growing demand of concerned triathletes.
Within a few years, the tri-bike was created, offering the triathlete aerodynamics, speed and muscular efficiency. And let us not forget the use of the smaller 650c wheels – a radical departure from the traditional 700c wheels. These smaller, lighter wheels also proved beneficial providing less rolling resistance allowing the rider to accelerate faster.
Which bike is better for a triathlete?
So, which one is better for a triathlete? It depends on your specific needs. If your priority is speed and aerodynamics, then a triathlon TT bike would be the best choice. However, if you value versatility and the ability to use the bike for training and other types of cycling, then a road bike may be a better choice.
For shorter distance triathlons like a Sprint or Olympic distance then a road bike will be a good choice but for longer distance triathlons like Half Iron or IRONMAN then maybe you should consider a triathlon TT style bike.
On mountainous or very hilly triathlon racecourses triathlon TT bikes can be difficult to handle and not as efficient as if you were riding a smooth, flat course. It’s worth looking at your race bike profile map to see what bike is better. Also, if you are racing a very hilly course then it’s using your triathlon bike in similar conditions replicating the ascents and descents to make sure your bike suits the conditions.
You can use the chart below to determine the best bike based on your race, course type, and budget.
Race | Course | Bike Flexibility | Money No Object |
Sprint | Flat/Undulating | Road Bike option to add clip-on tri-bars | Triathlon TT Bike |
Sprint | Very Hilly | Road Bike | High End Road Bike |
Olympic | Flat/Undulating | Road Bike option to add clip-on tri-bars | Triathlon TT Bike |
Olympic | Very Hilly | Road Bike | High End Road Bike |
Half Iron | Flat/Undulating | Road Bike with Clip-on Tri-Bars | Triathlon TT Bike |
Half Iron | Very Hilly | Road Bike with Clip-on Tri-Bars | Very High-End Road Bike |
IRONMAN | Flat/Undulating | Triathlon TT Bike | High End Triathlon TT Bike |
IRONMAN | Very Hilly | Road Bike with Clip-on Tri-Bars | Very High-End Road Bike |
Another consideration is if the race location is very windy as some triathlon bikes have deep section or disc type wheels which are notoriously difficult to handle in windy conditions. It’s always worth taking wheel options with you to your event if you think it may be windy on race day.
Ultimately, the decision between a road bike and a triathlon TT bike should be based on your individual needs and preferences. Both types of bikes have their own unique advantages, and the best choice will depend on your race goals, budget, and the type of triathlon they will be participating in.
Conclusion – What Bike is Best for You?
A road bike is a versatile option that can be used for training and other types of cycling, while a triathlon TT bike is specifically designed for speed and aerodynamics four use in triathlon races and time trails.
You should consider your own needs, preferences, and goals when choosing between these two types of bikes. What is your key race in the season? What distance is it and what is the bike course profile? What is your budget?
A compromise could be to fit clip-on tri bars to your road bike to “get aero” in your next race but check your race rules to see if they are allowed in your specific race.
Frequently Asked Questions
A triathlon TT bike, also known as a time trial bike, is a type of bike specifically designed for triathlons. It features an aerodynamic design and geometry that allows the rider to be in a more forward-leaning position and to rest their forearms on the bike, reducing wind resistance and increasing speed.
The main benefit of using a triathlon TT bike in a triathlon is its aerodynamic design, which can help to reduce wind resistance and increase speed. Its geometry also allows the rider to be in a more forward-leaning position, which can be more efficient for power transfer.
Triathlon TT bikes typically have an aerodynamic frame design, aero bars, and a more aggressive geometry. They also often have integrated brakes and shifting systems, and a more aerodynamic wheel design.
While a triathlon TT bike is designed specifically for triathlons and its geometry may not be as versatile as a road bike, it can be used for other types of cycling such as time trials, but it may not be as comfortable for long-distance riding.
No, triathlon TT bikes can be used by triathletes of all levels. However, it’s important to note that they require a different riding position and technique than a traditional road bike, so it’s a good idea to get comfortable with the bike before using it in a race.
The cost of a triathlon TT bike can vary widely depending on the brand and model. Entry-level models can start at around $2,000, while high-end models can cost over $10,000.
The riding position on a TT bike is more forward-leaning than on a traditional road bike, which can put more pressure on the rider’s hands and forearms. As a result, some riders may prefer a saddle that is designed to distribute pressure more evenly and provide additional support for the rider’s sit bones.
The most popular saddle for a TT bike are the ones that are designed for triathlons and time trials, which are typically long and narrow, with a cut-out or channel in the center to reduce pressure on the perineal area.
It’s always best to try different saddles and find the one that is most comfortable for you, and keep in mind that the saddle is also a personal preference and what may work for one rider may not work for another.
A standard road bike can be used in an IRONMAN triathlon, but it may not be the optimal choice.
IRONMAN triathlons consist of a 2.4-mile swim, a 112-mile bike ride, and a marathon (26.2-mile) run. While a standard road bike is certainly capable of completing the bike portion of the race, it may not be as aerodynamic or efficient as a triathlon time trial (TT) bike.
TT bikes are specifically designed for triathlons and have an aerodynamic design and geometry that allows the rider to be in a more forward-leaning position and to rest their forearms on the bike, reducing wind resistance and increasing speed.
Additionally, the riding position in a TT bike is more aggressive and aero dynamic than a road bike, which can help to minimize fatigue over the long course and make it more efficient for power transfer.
That being said, it is not impossible to complete an IRONMAN with a road bike, it’s just that a TT bike is designed to be more efficient and will give you an edge in terms of performance and speed. Ultimately, the choice of bike comes down to the individual’s preferences, bike route profile and race goals.
An aero helmet is not a requirement for riding a triathlon time trial (TT) bike, but it can be beneficial in terms of aerodynamics and speed.
Aero helmets are designed to reduce wind resistance and increase speed, by featuring a smooth, aerodynamic shape and minimal ventilation. They are especially beneficial when riding at high speeds and in windy conditions.
In a triathlon, every second counts, and wearing an aero helmet can help to minimize drag and make the rider more aerodynamic. This can be especially beneficial during the bike portion of the race, which is often the most time-sensitive segment.
An aero helmet is not a requirement, and many triathletes choose to wear a standard road helmet or a more ventilated helmet for comfort. Ultimately, the choice of helmet is a personal preference and depend on the rider’s own needs, preferences, and comfort level.
TT bikes are designed to be aerodynamic and efficient for racing in flat or rolling terrain, and they may not be the best choice for hilly or mountainous racing routes.
TT bikes have a more aggressive geometry, with the rider in a more forward-leaning position and aero bars that allow the rider to rest their forearms on the bike and reduce wind resistance. This riding position and geometry can be less efficient and less comfortable when climbing steep hills, as it puts more pressure on the rider’s hands and forearms and less weight on the pedals.
On hilly or mountainous routes, a road bike or a mountain bike with a more upright riding position and a wider range of gears would be more suitable. These bikes have a more relaxed riding position, and a wider range of gears which allows you to maintain a more consistent cadence and power output when climbing, which is more efficient for climbing steep hills.
Additionally, road and mountain bikes have more clearance for wider tires and suspension, which can provide better traction and control on steep and winding descents.
In summary, while TT bikes can be fast and efficient on flat or rolling terrain, they may not be the best choice for hilly or mountainous racing routes, and other type of bikes such as road or mountain bikes may be more suitable for these types of races.
Txs, very informative and I never had a bike so txs again!!!!
“dave” empfield? perhaps you meant Dan?