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Road cyclists and triathletes have never seen eye-to-eye. Perhaps it is the sleeveless jerseys or the lack of socks.
But when you dig a little deeper it is not just the clothes that are different, the bikes are too.
Let’s cast a suspicious eye across to the murky world of triathlons and find out the difference between a tri bike versus road bike.
There are lots of subtle differences but the main one can be found in the frame geometry. On triathlon bikes, the seat tube angle is usually between 76 and 78 degrees compared to 72 degrees on an average road bike. The steeper angle puts the triathlete in a more aerodynamic position.
Triathlon bikes are more comparable to time-trial machines used against the clock in the pro-peloton but even then there are some slight variations.
Road Bikes Vs. Triathlon Bikes: The Differences
Roadies and triathletes are very different beasts, especially as you move up the ranks to the professional level and the bikes they use reflect this.
Aside from the obvious difference of having to contend with a swim and a run ruining a nice day on the bike, triathlons are much more of an individual sport than road cycling.
Road cycling is more of a team sport where winning a race is as much about tactical prowess as it is about having the legs on the day.
It stands to reason then that the machines should be different. With no teammates to shelter you from the wind, triathletes need to reduce the effects of aerodynamic drag to stand any chance of standing on the podium.
Video: Triathlon Bike Vs Road Bike || The Key Differences
- Frame Angles – the frame angle on a road bike is shallower than a triathlon bike which puts the rider in a more comfortable, upright position.
- Drop handlebars – plenty of freedom to change position on the bike depending on the terrain.
The fundamental design of road bikes has evolved only sporadically over the years but why fix something that isn’t broken. They are designed to carry riders as far as possible on, as the name suggests, roads.
Compared to triathlon bikes, the frame geometry puts the rider in a more upright position that can be sustained comfortably for hours in the saddle without requiring a deep massage after a ride.
If you want speed, the drop style handlebars allow riders to tuck into a more aerodynamic position for sprinting to the nearest street sign.
Read more: Flat Vs. Drop bars – the differences
- Aerodynamic position – aero bars, deep carbon rims, and a steep seat tube angle put the rider in an efficient aerodynamic position.
- Storage – nutrition is hugely important and triathlon bikes usually have easy-to-reach, integrated storage for extra food and drink.
- Comfort – the position of the seat post is designed to take some of the strain off the hips and hamstrings and keep triathletes fresher for the run.
Triathlon bikes are built for the demands of the triathlon. Since drafting behind other riders is illegal in most triathlons every rider has to be as aerodynamic as possible.
With a steeper seat tube angle, aero bars, and deep carbon wheels, triathlon bikes can eke out significant time by cutting more efficiently through the wind.
So, triathlon bikes are the same as time trial machines? Not quite.
In a cycling time trial, the best ride is one where the rider crosses the line without an extra drop of energy in the tank. Everything is left out on the road. In a triathlon, however, the athlete has the added complication of stepping off the bike and quickly transitioning into a demanding run.
To keep them fresher for the run, triathlon bikes typically have a wider gap between the aero bars and the seat tube tends to be slightly further forward (or as much as the UCI rules allow) to help take the strain off the hips and hamstrings.
Triathlon bikes may also have extra compartments for nutrition, either integrated into the frame or using aftermarket products.
Read more: Using a commuter bike for a triathlon
Are Triathlon Bikes Faster Than Road Bikes?
Every cyclist has had to make peace with aerodynamic drag, that invisible force that keeps pushing you back. The faster you go, the more demoralizing it gets.
Once you hit 30mph on the bike, 90% of the power going into your pedals is used to overcome air resistance.
Without going into the physics of pressure drag and skin friction drag most cyclists intuitively know that making themselves smaller on the bike helps to cut through the air.
The frame geometry and tri-bars of triathlon bikes put the rider in a much more aerodynamic position by reducing the frontal area. Whilst there may be a power penalty in this more aerodynamic position, overall it can make a significant difference to the speed.
Combined with the more aerodynamic frame tubes and deep-section wheels, on a flat course, a triathlon bike will be faster than a road bike, everything else being equal.
It is not that simple though as these aerodynamic benefits come with a hefty weight disadvantage. When the road starts to go uphill, this extra weight and aggressive position on the bike will see the triathlete lose ground to the road cyclist.
Can I Use A Tri Bike As A Road Bike?
If you turn up to your local cycling club group ride with a triathlon bike you will be politely asked to leave. It is nothing personal.
It goes beyond the usual mistrust of triathletes and is a safety concern for other riders in the group.
They are also banned altogether in any sanctioned road or crit race and frowned upon in even the most relaxed Sportives.
Triathlon bikes are not meant for group rides as they don’t offer nearly enough control. Shifting and braking are harder and overall awareness is numbed due to the head-down riding position.
Even away from group rides, it is hard to make the case for using a triathlon bike as a regular road bike. They are stiff, uncomfortable, and unforgiving on long rides to the point where any pleasure could be lost.
Do You Need A Tri Bike For A Triathlon? Is A Tri Bike Worth It? Can I Just Use A Road Bike?
You do not need a tri bike to compete in a triathlon and could get to the start of the run on a penny-farthing if the rules allowed.
If you are dipping your toes into the triathlon world then it makes sense to use what you have and with a few simple modifications, a road bike can be competitive in a triathlon.
The simplest modification is to add clip-on aero bars to your road bike. This will allow you to almost mimic the aerodynamic position of a triathlon bike. These are easy to install but you will still have to rely on your regular road bike STI shifters. Studies have shown that this cheap modification can reduce your drag coefficient by 14%.
A more aero helmet and perhaps some deep-section wheels will further eat into the advantage of a dedicated triathlon bike.
The good news is that some, admittedly not very rigorous scientific experiments, have shown that having a dedicated aero bike might only give a marginal advantage unless you can push some serious watts.
If your goal is to finish the triathlon with a respectable time then there is no need to speed thousands of dollars on a dedicated triathlon bike that is more or less useless away from the event itself.
So when is a tri bike worth saving for?
If your goal is to stand on the podium in an IRONMAN event then there is no doubt about it; you need a triathlon bike and you will need to put in some serious training on it.
At this level the competition is fierce and the difference between the podium and everyone is else can be mere seconds.
Read more: Road Vs. Touring bike
Is A Road Bike Or Tri Bike Better?
Based on decades of experience, road bikes and triathlon bikes are each optimized for their disciplines. Neither is better than the other, simply better for a particular event.
There is no escaping the fact, that if you want to be competitive in triathlons and take your place on the podium then saving up your money for a dedicated triathlon bike could make the difference.
If you are just dipping your toes into the world of triathlon then, with a few simple adjustments, a road bike is more than good enough to get you to the finish line. Road bikes are much more versatile compared to triathlon bikes overall and are great, everyday machines.