Troy Lee Designs top-tier mountain bike helmet offers plenty of protection, uses premium throughout, and is extremely comfortable

Author: Erik Nilson / Updated: May 5, 2023
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Troy Lee Designs has a long-standing history of making some of the best mountain bike helmets on the market, and I’m happy to report that the A3 carries on the tradition. After a full season of use and abuse in the Pacific Northwest, I came away impressed with the TLD A3’s standout comfort, premium set of features, and robust construction. From gnarly enduro trails to quick after-work pedals, the Troy Lee Designs A3 helmet is the perfect companion.
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Troy Lee Designs A3 Helmet

Price: $220
Best Use: Trail, Enduro
Head Shape: Round Oval
Construction: In-mold
Virginia Tech Rating: 5 Stars
Impact Protection System: MIPS
Vents: 16
Weight (actual): 14.7 ounces
Pros:
– Premium build quality and very comfortable fit.
– Lots of extras included in the box.
Cons:
– A bit on the pricey side (although you get what you pay for).
– Ventilation is lacking.
Unboxing the Troy Lee Designs A3
With a premium price comes the expectation of a premium arrival, and the Troy Lee Designs A3 helmet does not disappoint. Safely packed in a robust cardboard box–which is much thicker than most I’ve recently tested–the top-tier lid is held securely in place by a padded floating insert. And with the additional foam block on the ceiling of the box, the A3 was delivered in perfect condition.

While the Troy Lee Designs A3 may command a high price, there are a number of included accessories that many other helmet manufactures omit, which helps increase its value. In the box you’ll find an additional liner kit for when the original gets nasty, and the fleece-lined helmet bag has mesh on one side that helps the helmet air out during transport. Troy Lee Designs also includes a couple of extra visor screws, a half page of stickers, and two extra EVA foam brow inserts. Add all that up and I feel like there’s easily $30 of accessories included with the TLD A3, which makes the $220 price a little easier to swallow.


Troy Lee Designs A3 Performance
Protection and Safety
While I don’t make a habit of testing a helmet’s effectiveness, the TLD A3 is filled with features and technology that inspires confidence to hit just about any feature on the mountain. Inside the Troy Lee Designs you’ll find a B-Series MIPS liner that integrates very nicely into the helmet and helps reduce rotational forces during a crash, and the combination of EPS and EPP foam aims to absorb both high- and low-speed impacts (a feature unique to the A3). It also receives a 5-star rating from Virginia Tech’s helmet research lab, and its deep fit provides more coverage than traditional XC lids. All in all, the Troy Lee Designs A3 checks all the boxes when it comes to protection and safety for a modern mountain bike helmet.

Comfort and Fit
Having logged thousands of miles in both the previous Troy Lee Designs A1 and A2 helmets, I can confidently say that the A3 is the most comfortable version yet. The liner and padding are plush without adding bulk, and the MIPS liner doesn’t interfere with comfort and remains silent on the trail. The 360 fit system offers a ton of microadjustments to dial in the perfect fit, and I particularly appreciate the easy-to-position chin strap splitters that minimize any earlobe-to-strap interference. All this adds up to a helmet that remains equally comfortable on quick lunchtime shreds as it does on grueling multi-hour rides. In summary, the Troy Lee Designs A3 is the most comfortable mountain bike helmet I’ve ever had the pleasure of riding in.


I ordered my standard size M/L in the Troy Lee Designs A3, which fits my 57 cm noggin very well and offers plenty of adjustment in either direction. In terms of head shape, I find the Troy Lee Designs helmet to be on the rounder end of the spectrum, similar to Giro’s Manifest Spherical. However, if your head is a bit more oval than round, then Fox’s Speedframe Pro might be a better fit for you as it’s slightly narrower in shape. Finally, POC’s Kortal Race MIPS is the narrowest of all and didn’t work for my slightly rounded head.
Ventilation
While the Troy Lee Designs A3 excels in many areas, ventilation is not one of them. It’s not the worst I’ve used, but it’s certainly not the best. The A3’s 16 vents, though an improvement over the older A2, are on the smaller side and they don’t allow air to flow particularly well. That being said, here in the Pacific Northwest, the A3 is the perfect companion for about 9 months out of the year. Only when temperatures rise above 80 degrees or so do I reach for better-ventilated helmets, like Fox’s Speedframe Pro. If your rides are generally cool in nature, then the Troy Lee Designs A3 should provide plenty of ventilation for your needs.

Eyewear Compatibility
During my time with the A3, I tested several different types and styles of glasses and I’m pleased to report that I experienced zero issues. The helmet didn’t push them down on my nose, which can be a problem with some helmets like the POC Kortal Race MIPS, and the glasses’ arms were easy to slide in and out as I removed them from my face. Although I’m not typically a half-shell and goggle type of rider, my Giro Blocks fit fine with the A3. As with most high-coverage half shells that prioritize protection, glasses storage is not a strong suit of the Troy Lee Designs. I was able to finagle them into the vents on the helmet, but it wasn’t a smooth process. If this is important to you, check out Oakley’s DRT5 helmet, which has little grippers specifically made for this purpose.

How Much Does the Troy Lee Designs A3 Weigh?
On my scale, the Troy Lee Designs A3 weighs 14.7 ounces in a size M/L, which is 0.8 ounces over the claimed weight and makes it one of the heavier high-coverage half-shell options. It’s 1.3 ounces heavier than the Fox Speedframe Pro (13.4 ounces) and outweighs the 14.2 ounce POC Kortal Race MIPS by half an ounce. Adding to the A3’s above-average weight is its solid feel, which isn’t necessarily a bad thing, but it’s noticeably more stout in hand when compared to the mountain bike helmets listed above. I’ll admit that I may be splitting hairs (see what I did there), but I also know from experience that on long rides extra ounces can add up. Having said all that, the standout comfort of the A3 makes it all but disappear on the trail and I wouldn’t let the weight scare you away from this standout performer.

Key Features of the Troy Lee Designs A3
MIPS Liner
The Troy Lee Designs A3 features a B-Series MIPS liner that integrates seamlessly into the helmet. Unlike other helmets I’ve tried over the years, the liner remains silent while descending trails at speed, doesn’t interfere with airflow, and hasn’t caught my hair yet. The B-Series version is also unique in that it is directly attached to the fit dial, offering a more streamlined finish (other versions utilize a two-piece design). There isn’t much to talk about with the MIPS liner, and that’s not a bad thing.

Fidlock Buckle
I didn’t really understand the allure of magnetic Fidlock buckles until I spent a good amount of time using them. It’s definitely not a revolutionary technology for helmets, but the quick clipping and one-handed operation have won me over. For reasons unknown–maybe it just makes me feel like a cool kid–I’m a fan of unbuckling my mountain bike helmets on long and slow fireroad climbs, and the Fidlock buckle happily obliges with minimal fuss.

Visor
Despite its minimalist looks, the Troy Lee Designs A3’s visor does a great job of blocking low-hanging branches and flying mud. The visor has three different positions to choose from, the material is thick and robust, and the center magnetic attachment point holds it securely in place. However, the magnets are a bit too strong for my liking, making it quite challenging to move and requires two hands to do so. If there is one complaint about the visor, this would be it. Overall, the visor works as intended and mostly goes unnoticed unless an adjustment is needed.


Fit Dial
The fit dial on the Troy Lee Designs A3 is one of the best in the business. The action is super smooth, it’s easy to operate with gloves on, and the 54 clicks of microadjustments allow you to achieve the perfect amount of tension. Also noteworthy is that the dial and B-Series MIPS liner are one piece (most are a two-piece design), which allows for even tension around the entire head. Unlike with the A2, which I often had to overtighten before dropping into a particularly rough section of trail, the A3 remains in place with minimal tightness.

Issues with the Troy Lee Designs A3
After using and abusing the Troy Lee Designs A3 helmet for an entire season, I’m happy to say that the helmet has held up extremely well. Despite a few off-the-bike moments, and hundreds of miles of use, the helmet looks as good as new. There are no noticeable signs of the liner delaminating, the fit dial still functions smoothly, and even after bouncing around in the back of my 4runner, the shell is free of any visible marks or scratches. I’ll be sure to update if anything changes, but for now, I’m thoroughly impressed with the overall package of the A3.

The Bottom Line
Starting with the original A1 (then the A2)–helmets that I’ve ridden thousands of miles in–Troy Lee Designs has long held a special place in my heart. They were one of the first to introduce the high-coverage half shell and I’m pleased to see that the A3 carries the torch as another phenomenal helmet. The A3’s high price may give some prospective buyers pause, but I can assure you it’s worth the extra coin. To date, the Troy Lee Designs A3 is one of the best mountain bike helmets I’ve ever used.
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How Does it Compare?
Product | Troy Lee Designs A3 | Fox Speedframe Pro | POC Kortal Race MIPS | Smith | Troy Lee Designs A2 |
Image | |||||
Price | $229 | $179 | $259 | $250 | $85 |
Best Use | Trail, Enduro | Trail, Enduro | Trail, Enduro | Trail, Enduro | Trail, Enduro |
Head Shape | Round Oval | Intermediate Oval | Long Oval | Intermediate Oval | Round Oval |
Construction | In-mold | In-mold | In-mold | In-mold | In-mold |
Virginia Tech Rating | N/A | ||||
Impact Protection System | MIPS | MIPS | MIPS | MIPS | MIPS |
Vents | 16 | 19 | 17 | 20 | 14 |
Visor | Yes, Adjustable | Yes, Adjustable | Yes, Adjustable | Yes, Adjustable | Yes, Adjustable |
E-bike Rated | No | No | Yes | No | No |
Weight | 14.7 oz. | 13.4 oz. | 14.1 oz. | 13.4 oz. | 12.4 oz. |
Shop Helmets |
Troy Lee Designs A3 vs. Fox Speedframe Pro
The Troy Lee Designs A3 and Fox Speedframe Pro (in-depth review here) are two of my favorite mountain bike helmets on the market. Both are extremely comfortable, have earned the highest safety ratings in Virginia Tech’s independent helmet research lab, and offer several premium features. Deciding between the two can be a challenge and it all depends on your ride plans for the day. If temps are high or it’s going to be a big day in the saddle, the lighter and better-ventilated Speedframe Pro is the way to go. But for cooler temps where a slight bump in coverage and comfort is desired, the TLD A3’s deeper fit and more plush liner is a better choice. Price is also a factor, with the Fox costing about $50 less than the TLD. However, the A3 includes a carrying bag, extra liner, visor screws, and stickers. Ultimately, choosing between these two great helmets comes down to your top priorities.

Troy Lee Designs A3 vs. POC Kortal Race MIPS
The Troy Lee Designs A3 and POC Kortal Race MIPS are two standout helmets for aggressive trail and enduro riding. While both offer loads of coverage and feature MIPS liners to help reduce rotational forces in a crash, there are notable differences between the two. The A3 has a much rounder fit and features a more plush padded liner, making it the more comfortable option overall (for my head). In contrast, the Kortal Race MIPS is narrower and feature-packed, with a RECCO location reflector and NFC medical ID functionality. It also meets the Dutch NTA 8776 helmet standard, which makes it a great option for those who ride electric mountain bikes. When choosing between these two lids, it ultimately comes down to personal preference and the specific needs of the individual rider. For example, those who have rounder heads will likely prefer the A3, while riders who value unique tech features (and have a narrow noggin) will prefer the Kortal Race MIPS.

Troy Lee Designs A3 vs. Smith Forefront 2
Smith’s Forefront 2 is a popular choice for mountain bikers, thanks to its comfortable fit, lightweight design, and good looks. Similar to the Troy Lee Designs A3, the Smith features a MIPS liner and adjustable visor, and it is available in a variety of color combinations. However, the A3 surpasses the Forefront 2 in almost every way. It has better ventilation (since the Forefront 2’s Koroyd technology blocks airflow), and comes with a number of accessories like an additional liner, extra visor screws, and a travel bag. Moreover, the A3’s liner is considerably more plush than the Forefront 2’s, making it a much more comfortable helmet. The final nail in the Smith’s coffin is that the TLD costs about $30 less. Unless you can find a killer deal on the Forefront 2 and you don’t mind an extra sweaty head, then the Troy Lee Designs A3 is the better choice.

Troy Lee Designs A3 vs. Troy Lee Designs A2
One final consideration is the predecessor of the A3, the Troy Lee Designs A2. Although it may have originally launched in 2017, its comfortable fit, MIPS liner, and deep coverage make it an excellent option. It also receives a 5-star rating from Virginia Tech’s independent helmet research lab, showing that it can still compete with newer options. Finally, the A2 is regularly on sale for less than $100, which makes it an incredible value. Having said that, the A2 omits some of the premium features found on the A3 (like a magnetic Fidlock buckle) and it isn’t quite as comfortable overall. The A3 also runs a bit cooler and its one-piece B-Series MIPS liner makes for a more seamless and better fit compared to the A2. The new A3 is easily the better helmet, but for less than half the price, the Troy Lee Designs A2 is still a smart choice.

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