Which is Better – Road Bike or Triathlon Bike?

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.

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.

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