The right cycling helmet for racing can give you a valuable performance edge

On race-day, your choice of cycling helmet can have a large influence on your triathlon performance. 

The fastest option could save you precious minutes over longer triathlon distances. Equally, a poor decision in hot conditions could lead to disastrous overheating and dehydration. 

In this article, we’ll explain which type of helmet is best for which races from the range of aero helmets, road helmets, and TT helmets available on the market. If you want a free and instant edge to improve your triathlon performance, you’re in the right place.

Time-trial helmets

Although the time-trials helmets are generally the fastest type of bike helmet for triathlons, the pros rarely race in them these days and there is an important reason for that.

Aero helmets can feel hot to cycle in and require the right conditions to reap the benefits. They’re best suited to flat and fast courses in windless conditions, which can be hard to find unless you’re competing in a TT. Alternatively, a normal aero cycling helmet is usually better ventilated and can sometimes be almost as aerodynamic. Plus, let’s not sniff at the difference in price tag!

However, if you own a TT helmet, it still might be worth wearing it if cooler conditions are forecast for race day and the right course presents itself. 

Aero road helmets

The fastest aero road helmets only give away a handful of watts to heavier and hotter TT helmets. As a result, they’ve become the default race-day cycling helmet choice for pro triathletes.

If you aim to buy only one cycling helmet for training and racing in triathlons and cycling events, make it an aero helmet. Unless you ride in the hottest conditions, you’re unlikely to overheat. And in winter, fewer vents are welcome. 

Compared to the best road bike helmets for triathlon, modern aero helmets are much more aerodynamic. We’ve calculated in strict wind tunnel conditions that an aero helmet can save you 44 seconds over a 40km bike leg, making it one of the best instant ways to get more aero on a budget. 

Meanwhile, aero helmets are barely heavier and not much less cooler than traditional vented helmets. 

Road bike helmets

All this is not to say road bike helmets don’t have their place in triathlon. After all, the key thing is that a helmet meets the relevant safety standards. The best budget bike helmets will protect your head in the event of a crash and that, after all, is the most important quality in a triathlon helmet.

Unless you’re targeting a fast triathlon time or racing at the pointy end of the sport, if you already own a road bike helmet, it’s probably not worth upgrading to something more aerodynamic. 

But when the road points up, such as in the Alpe d’Huez triathlon, a road bike helmet could be your best race-day cycling helmet choice.

When the gradients top 8%, weight beats aero and ventilation is essential. The temperature during the summer in the Alps or Pyrenees can become almost unbearably high. 

If you do descend in a mountainous triathlon, you’ll likely be going as fast as you’re comfortable to go. Therefore, an aero helmet won’t help unless you’re sat on the top tube and hugging your stem at 60mph.

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