Reviews You Can Rely On

Troy Lee Designs D3 Carbon MIPS Review

Quality and comfort is the name of the game with the D3 Carbon
troy lee designs d3 carbon mips downhill helmet review
Credit: Troy Lee
Price:  $495 List
Manufacturer:   Troy Lee Designs
By Dustin Schaad ⋅ Review Editor  ⋅  Apr 20, 2018
  • Comfort - 25% 8.0
  • Protection - 20% 9.0
  • Weight - 20% 7.0
  • Ventilation - 15% 8.0
  • Visor - 10% 8.0
  • Durability - 10% 8.0

Our Verdict

The Troy Lee Designs Carbon D3 is one of our highest rated helmets. The D3 is Troy Lee's no-holds-barred, full-face downhill helmet. The Carbon version replaces the composite shell of the Troy Lee D3 with a carbon shell. The key features we love about the D3 and D3 Carbon are the excellent ventilation system, the visor, high-quality materials, storage bag, extra visor, and comfortable wicking interior padding. The carbon shell shaves a few ounces off the helmet's weight. The reduced weight adds even more comfort to this helmet. Essentially we are saying the D3 Carbon is an excellent pick for a full-face lid.
Adjustable visor
Quality construction
Premium materials
Excellent ventilation system
Potential durability issues
Product Update
The D3 Carbon is no longer offered for the 2020 model year. It has been replaced by the D3 Fiberlite which looks identical but has a lightweight fiberglass shell. It retails for $249. Troy Lee Designs also makes the D4 Carbon and the D4 Composite which are strikingly similar to the D3 Carbon model we tested. October 2019

Our Analysis and Test Results

The D3 Carbon is on the head of every Troy Lee Designs team rider. This was the helmet Semenuk was wearing when he won Joyride. This was the helmet Cam Zink was wearing when he stomped the flat drop backflip at the Red Bull Rampage. Peat, Hill, Fairclough, and Gwin all wear this helmet. If you are wondering what some of the world's best mountain bikers are wearing, its the D3 Carbon.

Performance Comparison

troy lee designs d3 carbon mips downhill helmet review - the troy lee designs d3 in action.
The Troy Lee Designs D3 in action.
Credit: dustin schaad


The D3 Carbon ranked high in our testing for comfort. The strategically placed interior chin bar shock pads set the stage for how precise the designers and athletes worked together. After the hot, humid days riding the bike park, the removable and washable liner was important. The liner is built with Coolmax, and Dri-Lex moisture-wicking material was key to keeping the smell out and the coolness on point. The contoured 3D cheek pads fit anatomically and work perfectly.

troy lee designs d3 carbon mips downhill helmet review - rocks and grease shouldn't deter you with this helmet.
Rocks and grease shouldn't deter you with this helmet.
Credit: dustin schaad

The fit is a component of comfort in a helmet, but every head is different. We feel that this helmet has all of the elements for comfort; however, it did not fit all of our testers perfectly. We concluded that it has a rounded shape rather than an oval shape. Our oval-headed testers upsized the helmet to get an appropriate front to back fit, which resulted in a slightly baggy side-to-side fit. If you have a round head, this is the helmet for you. If you are average to oval-headed, then you may want to try this helmet on before you buy. The good news is that the D3 is available in five sizes, and getting the right fit is a lot more likely compared to a helmet that only comes in three sizes.

troy lee designs d3 carbon mips downhill helmet review - front view of the tld d3
Front view of the TLD D3
Credit: dustin schaad


The D3 is certified by more standards than any other helmet we tested. It meets the CPSC 1203 and CE EN 1078, the minimum standards for bike helmets. It is also certified to the more stringent ASTM-F1952, which we feel is the certification downhill riders should look for in a helmet. In addition to these three, it also meets a variety of other standards including CE EN 1077 for skiing and snowboarding, which is something to consider if you are looking for one helmet for a variety of sports.

The inner polystyrene is laced with strips of very dense closed-cell foam that is supposed to help absorb small impacts. Large impacts are absorbed by the usual destruction of the polystyrene foam. Troy Lee Designs doesn't label the D3 as a multi-impact helmet, but we like the idea that minor impacts are absorbed by something other than the destruction of the polystyrene. We understand that nobody is going to replace a $375 helmet after a minor impact for fear of comprised safety. As always, if you take a whopper on the head, consider that you got your money's worth and replace your helmet.

The cheek pads are backed with velcro that attaches them to the inside of the helmet, which makes them easy to both remove and re-install. These pads have red fabric tabs that protrude from the bottom of each pad to instruct emergency rescuers how to quickly remove them from the helmet before removing the helmet from an injured person's head. This may allow a trained rescuer to remove the helmet with less movement of the head and neck, which could minimize secondary injuries to the spine. We see this as an added safety feature that we hope nobody has to use.

troy lee designs d3 carbon mips downhill helmet review - slab riding in canada with the d3
Slab riding in Canada with the D3
Credit: dustin schaad


The D3 weighs in around average in our test at 38.8-ounces. With all the great features the D3 offers that doesn't bother us much. The more they shave off, the less protective the helmet becomes.


This helmet scored about average for overall ventilation. This is impressive considering this substantial helmet fits more securely than most. Protective and secure is not usually synonymous with being well-ventilated, but this helmet can stay cool with a remarkably well-designed ventilation system. For starters, it has the largest number of vents of the helmets we evaluated, with 20.

troy lee designs d3 carbon mips downhill helmet review - sometimes super high speeds call for the use of a full face.
Sometimes super high speeds call for the use of a full face.
Credit: dustin schaad

Troy Lee labels 14 of these vents as intake ports and the remaining six as exhaust ports. At the front of the helmet, the airflow starts with intake vents that are molded into the vinyl gasket that lines the face opening. These intake vents are linked to deep air channels molded into the polystyrene. Between the head and the polystyrene foam is inner padding that has sections of mesh to allow for heat transfer from the head to the air flowing through the helmet. All of this adds up to perceptible airflow through the helmet, which isn't something we can say for many of the lids we tested.

troy lee designs d3 carbon mips downhill helmet review - mouth vents to help air pass in and out.
Mouth vents to help air pass in and out.
Credit: dustin schaad


The D3's visor scored the second highest in our test and is nearly perfect in our opinion.

troy lee designs d3 carbon mips downhill helmet review - side view of the tld d3
Side view of the TLD D3
Credit: dustin schaad

The visor is both long and wide enough to shield the eyes from any angle of sun, mud, or rain. It also completes this helmet's very moto look, so don't even think of rolling Rogatkin-style without it.

troy lee designs d3 carbon mips downhill helmet review - tld visor screws
TLD Visor screws
Credit: dustin schaad

The visor is attached with titanium screws, which Troy Lee claims save a little weight. These screws are very nicely finished and are durable. We doubt that the weight savings is very significant relative to the total weight of the helmet.

troy lee designs d3 carbon mips downhill helmet review - the visor of the troy lee designs helmet.
The visor of the Troy Lee Designs helmet.
Credit: dustin schaad

In addition to the screws on either side, the visor is also secured by a plastic thumbscrew which passes through a slider beneath the center of the visor. We found that this method of securing the visor is more natural to manipulate on the fly than visors attached and secured with just two screws.

troy lee designs d3 carbon mips downhill helmet review - tld middle visor screw
TLD Middle Visor screw
Credit: dustin schaad

Troy Lee also includes a second color-matched visor so you will have a back-up if you damage the original in a crash. If you find yourself needing another visor, you can buy one on the Troy Lee website for $40 - while you contemplate why you crash so much.


The TLD landed a little below average on our list for durability. Our biggest durability concern is that the plastic around the rim of the chin guard started to delaminate within a few weeks of testing. The delaminating section is located exactly where you grab the helmet while slipping it on or off. Otherwise, we have little to complain about. Did we mention the "D" rings and helmet attachment screws are made of titanium so that they don't corrode? Everything about this helmet is quality down to the included storage bag.

troy lee designs d3 carbon mips downhill helmet review - plastic on the inside of the carbon detaching
Plastic on the inside of the carbon detaching
Credit: dustin schaad


This deluxe helmet comes with several notable extras. It comes with an extra color-matched visor that we think is very useful since visors sometimes don't survive minor crashes that leave the rest of the helmet intact. Ours also came with a zippered bag that is large enough to hold extra gear like goggles, gloves, or extra lenses.

troy lee designs d3 carbon mips downhill helmet review - feel free to get rad with the troy lee designs d3 helmet on your head.
Feel free to get rad with the Troy Lee Designs D3 helmet on your head.
Credit: dustin schaad


The overall carbon downhill helmet market today is all priced fairly close - they're flat expensive. They all range from $400 - $500, based on demand, not necessarily the supply. You can buy a mountain bike for $500; it may not be the best bike on the trail, but if you spend another $500 on a new carbon lid, you'll be the most stylish rider on the trail.


This is one of our favorite carbon downhill helmets. The sizing can be a little funky if you have an oval-shaped head so try it on before you buy. If you can swing the price, we don't think you will be disappointed. You may also be able to swoop a deal by using our price finder tool at the top right.

Dustin Schaad
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