Words by Drew Rohde | Photos by Dusten Ryen
Video by Brian Niles / Treeline Cinematic

When it comes to mountain bike helmets, options have changed for the better in recent years. With the addition of pedal-friendly full faces like the 100% Trajecta, riders no longer have to pick between a traditional open-face helmet like the 100% Altis, or a hot, heavy downhill helmet. Ten years ago you had two very distinct helmet categories: the open-face “Trail lid”; or a downhill full-face helmet, and to be fair, trail bikes weren’t really capable of tackling downhill bike terrain they can today. The helmet you choose is largely dictated by the bike you are pulling out of the garage. Back then if you were lining yourself up for a day of hucking or charging through rock gardens on your dual crown downhill machine, you’d reach for that big moto-inspired full-face; and if you were going to be pedaling up a hill you’d take the lightweight cross country shell.  

Since the line between XC and DH riding has blurred significantly, as technologies and geometries have evolved and with them the downhill capabilities of bikes you still want to climb on, protection has had to evolve too. This has led to riders regularly ripping their trail bikes down tracks that were once reserved exclusively for full-face demanding DH bikes. Protection companies and now these slimmed down full-face are becoming more prevalent at the trailheads as riders look for additional safety and protection while still wanting to put in big miles.   

Though every effort has been made to make these enduro, pedal-friendly full-face helmets as light and breathable as possible, there is still going to be some inevitable drawbacks compared to their open-face alternatives. These are mainly the weight and overall heat inside the helmet, which is particularly noticeable on the longer grueling climbs, so the open face will always have its place when the risks are lower or the ride is particularly pedal-intensive in a hotter climate. Though we generally try to stretch our budget as high as it will go when it comes to purchasing a helmet to get the most ventilated option possible, there’s no ignoring the fact that a full-face helmet is always going to cost a chunk more than a comparable open-face lid. 

We’ve been evaluating several helmets in both categories from brands like Smith, Giro and 100% before publishing this feature. Acorss the board feedback is similar and while some helmets do some things better than others, the 100% Altis is a great representation of a comfortable and affordable high tech trail helmet while the 100% Trajecta is a higher end offering for enduro mouniian bikers wanting more. All helmets we tested performed rather well as a whole, but which option is right for you?  

As you may expect from two helmets made by the same company with crossover in their intended uses, there are some shared elements between the two helmets in the form of the Smartshock Rotational impact protection system and the anti-microbial moisture wicking pads. But that’s about where the similarities end between the two helmets, as you’ll find out below.

100% Trajecta Full Face

100% Trajecta w/Fidlock
The Trajecta is 100%’s enduro and all-mountain full-face helmet. The main shell of the helmet is a multi-density EPS foam injection molded with polycarbonate, in which sits their 13-point Smartshock rotational protective system. This shell is available in two sizes (S/M and L/XL), and the fit is then fine-tuned with the moisture wicking anti-microbial padding in classic full-face style. Twenty-four ventilation ports channel air around the head in a bid to minimize the heat buildup in use. The chin bar features a significant number of air channels to reduce the “hot breath” feeling that plagued full faces of old, and features patent pending integration to offer the necessary protection without adding bulk or excess weight. The visor is multi-point adjustable for eyewear compatibility and to maximize vision. The 2021 Trajecta now features a Fidlock SNAP magnetic buckle to make fastening and removing the helmet as easy as possible. This feature list racks up to a price of $250, with a range of six colors to suit most preferences. 

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100% Altis Half Shell Helmet

100% Altis
The Altis is 100%’s wallet-conscious yet feature packed open-face trail helmet that we recently reviewed here. A high-density EPS shell molded with polycarbonate is offered in 3 sizes (XS/S, S/M, L/XL) and is lined with an 11-point Smartshock rotational protective system. This shell is tailored to offer expanded coverage whilst remaining lightweight, and features 14 ventilation ports to take care of airflow. An adjustable ratcheting fitment system fine-tunes the fit to the head in classic open-face style, with a washable moisture-wicking anti-microbial liner. As with the Trajecta the visor is adjustable to stow eyewear or block out the sun, and a standard Nexus push release snap buckle is called upon to keep it in place on your chin. 100% has worked some magic to offer the feature-packed Altis for the $100 price point, meaning you can retain the rotational protective features of most expensive lids, with 6 colorways offered from subdued to striking.  

While both helmets are comfortable for the respective categories, there is no denying that when comparing a full-face to an open face, the difference is real. Depending on how slow you climb, and how it is outside, the difference could be rather minimal or lead you to buckling the helmet on your bars or hydration pack to climb without a lid.  

For us the biggest difference was the weight. Most of our climbs in pedal-friendly full-face helmets are on eMTBs so the speeds are high enough to keep air flowing through. If we were slugging up a long, hot fire road in Los Angeles then we’d likely be strapping this thing to our back or hanging it off the bars…or selecting the Altis and hoping we’d keep our face off the ground on the way back down.  

Of course, the compromise in choosing the Altis is that our coverage, and therefore, our confidence drops and we tend to ride a bit more cautiously. Stitches aren’t cheap, and neither are dentists. Don’t get us wrong, we like the Altis quite a bit, and our recent review says so, the problem isn’t the helmet itself, but the grey zone between DH and trail riding and that have us riding harder and faster down hill but without the facial protection we’re used to in downhill helmets.  

When comparing the 100% Trajecta to other helmets like the Smith MainlineFox ProFrame or iXS Trigger, it’s between 50-80 grams heavier, and after a few hours on the trail it’s noticeable. Ventilation however, is definitely impressive with the Trajecta and we think it holds it’s own in the category. When it comes to looks, comfort and a feeling of security inside the helmet, we’d definitely say the 100% Trajecta is near the top of our list. It looks great, fits nicely and we’d definitely feel more comfortable putting this helmet on for some occasional bike park laps compared to an iXS Trigger.  

We’d say it’s more of a downhiller’s trail helmet than a trail rider’s full face, which is what helmets like the iXS Trigger or Kali Invader would be. If you’re an aggressive rider who wants to get a downhill helmet style, all-day comfort but are prepared for the added heat and weight of a full-face on the climbs, the 100% Trajecta is very much on our recommendation list. If you’re looking for a lighter, more breathable lid some of the options above could be better for you, but we’d put this helmet on par with the Smith Mainline, which is one of our absolute favorites. It is however a bit heavier, which could be an issue for some more than others.    

The Wolf’s Last Word

In life, compromise is the name of the game and when it comes time to choose a helmet, like your bike, you’re going to need to make choices. Luckily helmets are a bit more affordable than bikes so owning more than one isn’t totally crazy. Ultimately, we’d all like to own specific tools for specific jobs, but we realize that sometimes we’ve only got the budget for a do-it-all piece of kit and if that’s the case, making the decision on a helmet boils down to how much safety you want versus how much of a comfort-penalty are you prepared to make. For our crew, we’ve been gravitating to pedal-friendly full-face helmets more and more and we’re happy to see more and better options entering the market.


Altis Price: $100
Weight: 366g 

Trajecta Price: $250
Weight: 887g 

Website: 100percent.com

Disclosure: Our team selects all of the products we review and do so with honesty and objectivity in mind. Some of the products we receive come directly from Competitive Cyclist, who also value our readers and have offered them a 15% discount (exclusions apply) on their first purchase by using LOAMWOLF15. Through this program we may also receive a small commission at no cost to you. Thanks for your support, TLW.


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