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If you’re thinking of doing your first triathlon but don’t have a triathlon bike, what do you do?
Maybe you only have a knockaround commuter bike or hybrid in the garage. You might feel self-conscious about it and wonder if you’ll look out of place.
A big question often asked is if a commuter, hybrid or mountain bike can be used in a triathlon. The short answer is YES.
But there’s a few dependencies…
This article tells you how to use any bike, within reason, to make your triathlon debut.
What Is A Typical Triathlon Bike?
A triathlon bike is one which places you in an aerodynamic position. It reduces your frontal area by putting your arms directly in front of the torso. It also promotes a lower torso position.
Below are some of the characteristics of a triathlon bike.
The geometry of a triathlon bike is aggressive, but it’s not as aggressive as a TT bike.
A chief difference between a triathlon bike and a road bike or a TT bike lies in the seat tube angle (STA). A triathlete will often prefer a steeper STA because it’s proven to help the transition between biking and running. It’s easier on the hamstrings.
The seat tube angle in a dedicated triathlon bike may be between 78 and 80 degrees, compared to 70 and 76 degrees in a road or TT bike.
A triathlon bike will typically have a shorter top tube length than a road bike, and a lower head tube. Compared to a TT bike, a triathlon bike allows more for comfort and favors a slightly higher rider position.
You might not “slam the stem” on a triathlon bike for the above reason. How low the front of the bike should be depends on the length of the ride and how long you can tolerate the position. Discomfort will slow you down.
Another chief difference between a triathlon bike and a road bike is the handlebar. The former has what is known as “tri bars” or “aero bars”.
On a dedicated triathlon or TT bike, the handlebar won’t have drops like a road bike. A base bar houses the brakes and the all-important bar extensions that stick out from the center.
Two pads positioned at the rear of the bar extensions (atop the base bar) support some of the rider’s weight as he/she leans forward into an aero position.
Riders will hold the two bar extensions on flat stretches of road to achieve the most aero position possible. Only when cornering or negotiating hills will they usually come off the extension bars for access to brakes and better control over steering.
The saddle on a triathlon bike may also differ wildly from most other saddles. Like the saddle of a TT bike, it will be designed for a pelvis that is rotated forward.
Rotating the pelvis forward for a low position on the bike makes the rear points of contact narrower. Rather than resting on the saddle at the “sit bones” (ischial tuberosity), a triathlete engages with it at the pubic rami, further into the pubic arch.
The described forward position potentially places more pressure on the soft tissues of the perineum. A triathlon saddle has to mitigate for this in its design and allow for the narrower points of contact.
How will a triathlete’s saddle look, then? Here are some typical attributes:
- Shorter – a triathlete is unlikely to sit in a rearward position or change position as much on the bike. Thus, the saddle will often be shorter.
- Cutout – there is a pressure-relief channel or cutout in triathlon saddles to relieve perineum pressure. Cutouts often extend to the nose (front) of the saddle.
- Shape – there is likely to be more width towards the front of the saddle and less at the rear, in line with the rotated rider position.
- Nose – the nose of a triathlon or TT saddle will typically be more padded than that of a regular saddle. It may also be reinforced to support more weight.
- Padding – overall padding may be denser than many road saddles, as triathletes wear shorts with a thinner chamois or no chamois at all.
It’s worth noting that saddles are still a personal thing, even when they’re designed for a specific type of riding. Some will need a wider saddle for adequate support at contact points. Others will need a narrower saddle for sufficient thigh clearance.
Video: Saddles For Triathletes
How You Can Set Up A Hybrid Or Commuter Bike For A Triathlon
Although a “tri” (triathlon) bike has a distinctive frame geometry, you can adapt a commuter bike or hybrid for a triathlon. Plenty of people do it in triathlons, particularly in sprint triathlons where the distances covered are modest.
When transforming your bike into a tri machine, the points on the bike that you or the road make contact with are crucial.
Tires are one of the few things you can change on a bike that will make you appreciably faster for the same level of fitness. At least, you’ll notice it if you go from slow, puncture-resistant tires to fast tires.
If your commuter bike is a road bike, chances are you’ll have chosen tires for their puncture resistance. Installing a pair of “performance” tires will make you faster. And you’ll feel the extra speed, which is worth something psychologically.
Continental GP 5000 tires are extremely fast without being overly delicate, so you’d be unlucky to puncture on them during an event. They’re also one of the most aero tires on the market, though you needn’t concern yourself with that on a first triathlon.
If you can’t afford new tires for a commuting road bike, don’t worry! The difference they’ll make isn’t huge, especially over a short distance.
Should your existing bike be a hybrid, city bike or MTB, look at the tread of the tires. If it’s a knobby tire designed for rough surfaces, switch it for a slick tire.
You probably won’t be able to fit a fast road tire onto another type of bike (e.g., a 29er MTB or hybrid), as the wheel’s rim width will be too wide. A Schwalbe Big Apple tire from the performance line might do. Pick the narrowest tire the rim will safely take.
Switching tires on a bike with knobby tires is more critical than switching tires on a road bike. You’ll be very inefficient riding off-road tires on the road.
Video: Can You Use A Mountain Bike In A Triathlon?
Fit A Tri Handlebar (Clip-on Bar Extensions)
You’ll make yourself faster on a road bike and even a hybrid bike or MTB by getting into a more aero position. You can do this by installing clip-on bar extensions, also known as clip-on tri bars or aero bars. These are inexpensive.
A clip-on tri bar is common on a road bike for amateur triathletes. It’s less orthodox on other types of bike, but it is sometimes fitted to hybrids and MTBs.
Theoretically, regardless of bike type, you’re reducing your frontal area with aero bars and making yourself faster as a result. No matter which type of bike you attach aero bars to, you must practice on them extensively before a triathlon.
Fitting a tri bar to the front of a road commuter bike may necessitate a saddle adjustment, though many riders skip this. You’d typically move the saddle forward, raise it slightly to compensate for the new position and angle the nose down a little.
Aero bars will make you around 1-2 mph faster. That’s a lot, as marginal gains go.
Do I Need To Change Saddle?
Whether you need to change saddles for a triathlon is hard to predict. It will largely depend on what you already have and the nature of the triathlon.
Many road saddles have things in common with Triathlon/TT saddles, like the cut-out to reduce perineum pressure. Depending on the shape of the saddle and your position on it, you may be able to rotate your pelvis without causing undue discomfort.
A road saddle that is wide at the rear and quickly transitions to narrow with an unpadded nose may be uncomfortable for a triathlon. (See typical triathlon saddle qualities already listed.) Accommodating that forward position is key.
The longer top tube of a road bike may force you towards the front of the saddle in your tri position. This could cause you pain, particularly on a road-bike saddle over long distances. Over the 12.4 miles of a sprint triathlon, you might get away with it.
Read more: Guide to bike commuting
Whatever bike you have available for a triathlon will probably suffice. The longer the bike ride, the more you must pay attention to comfort. Naturally, training for the event on your tri-adapted bike will tell you how doable it is.
The biggest change you’ll make to your bike’s speed will come from adding clip-on aero bars and switching the tires. If your commuter is a road bike, the tires are less critical. Ditch fat, knobby tires for any hope of decent speed on asphalt.
Adjust and/or change your saddle as required. Good luck!