509 Mach V Carbon Helmet Review [Full-Face Protection]

509 Mach V Carbon Motorcycle Helmet Review: Price

Last year, 509 expanded from its snow and off-road gear lines into street motorcycle apparel. We have tested the 509 @One motorcycle jacket and the Mach III Carbon full-face helmet. Now, we don the 509 Mach V Carbon helmet and go for some rides.

The 509 Mach V Carbon motorcycle helmet has a carbon fiber shell construction that enables light weight and is part of the impact protection system that meets the U.S. DOT FMVSS 218 helmet safety standard and the much stricter ECE 22.06 standard.

The standard clear polycarbonate shield is dual-pane and resistant to fogging and scratches.

With the Blacktop colorway and the clear gel surface that reveals the weave of that carbon fiber shell, the quality of the construction is clear and visible. The payoff of carbon fiber is light weight with great strength. Weighing in at only 3.84 pounds, the Mach V is easy to wear all day long.

The radical styling of the Mach V helmet is an attention-grabber. The standard clear face shield extends down to the bottom margin of the chin bar and has an easy-to-use lift tab at the point. There, it locks onto a small, molded catch that operates smoothly and easily, and stays in the desired position.

509 Mach V Carbon Motorcycle Helmet Review: MSRP
With the Fire Mirror faceshield, forward-mounted venturi ventilation intakes, wide, hood-scoop crown vent, and Blacktop color scheme, the 509 Mach V Carbon full-face helmet looks like it would be at home on an F-22 Raptor pilot or on the track as easily as on your daily rider.

We included the optional Fire Mirror reflective shield in this 509 Mach V Carbon helmet review. On days with severe clear skies, it earned its keep by easing the need to squint and adding a shimmering, high-tech look to the helmet. The light smoke tint comes in handy, as there is no internal drop-down sunshield. Changing shields is relatively easy without tools, though not without some problems; more on that later. In all, there are four additional shield options.

The dual-pane fog and scratch-resistant shields are marked as compliant with ECE 22.06 with the mark E-11 (11 indicating U.K.). That means the tinted/mirrored shields must allow a transmittance of ≥80 percent of the standard for incident light. In addition, the tint or coating on the shield cannot alter color perception. As a result, they do not appear as dark as some non-ECE-approved shields. When the riding weather turned much cooler, shield fogging was not an issue.

The point of the shield is flanked by the intake vents for the closable venturi ventilation system that echoes the appearance of F-22 Raptor intakes. A wide hood-scoop closable vent on the 509 Mach V Carbon helmet’s crown brings good topside airflow.

Instead of the typical round curve down to the rear from the crown, the line of the helmet tapers to a wide and deep rear spoiler. Three red automotive-style reflectors and twin outlet vents are tucked under the spoiler. Below them is a lateral rigidity ridge to strengthen the shell further, and the bottom edge of the shell is also flared out.

The sculpted shape of the shell works well aerodynamically. On several days, I rode in high, swirling winds, and the 509 Mach V Carbon resisted buffeting and lift, even at interstate speeds.

509 Mach V Carbon Motorcycle Helmet Review: For Sale
The comfort lining is plush, comfortable, and washable. However, it lacks emergency quick-release cheek pads.

The comfort liner is a plush mesh of 85 percent nylon and 15 percent spandex. In size XL (61-62 cm), the fit for me is snug, competition-grade, and comfortable. To accommodate riders who prefer a little roomier fit, half-thickness cheek pads are included. Wearing glasses works quite well, even though the padding is not recessed for eyeglass compatibility.

Ventilation is effective from the crown vent on the 509 Mach V Carbon. The vent opens with a single slide control that is easily operated with gloves on. Although a small amount of air inflow occurs when the shutter is closed, there is no whistle or buzzing from the shutter in any position.

The side venturi vents operate with small slide controls inside the chin bar. The effectiveness of the venturi venting system is a little more challenging to assess. Using the principle of the Venturi effect, the air inflow with the vents open from the large intakes to the much smaller air channels, one might expect the feel of high-volume airflow into the helmet.

However, as happens in the venturi of a carburetor, as the air moves from a larger opening into a constriction, airspeed increases, and air pressure in the constricted channel drops. This creates a slight negative pressure in the constricted portion. This draws warm, moist air from the helmet interior and exhausts it out the back of the vent.

As a result, the large intakes on the 509 Mach V Carbon do not create a perceptible rush of air into the helmet. It is subtle, using airflow across the small interior openings to draw interior air out. The advantage of this approach is that the effect can be achieved without the flow of cold air on chilly rides. Overall, in several days of riding in unseasonably warm weather, the interior never felt overheated; you just don’t feel the inrush of air like you do from the crown vent.

Helmet interior noise is about the same with the vents all open or all closed and is not particularly bothersome.

509 Mach V Carbon Motorcycle Helmet Review: Fidlock
The Fidlock magnetic chin strap buckle is a quick and convenient alternative to the traditional double D-ring.

As with the 509 Mach III Carbon full-face helmet, the Mach V has the magnetic Fidlock chin strap buckle. It is a welcome advancement from the old double D-ring buckle. At first, using the Fidlock seems a little, well, fiddly. However, once you do it a few times, it literally buckles itself. Giving the chin strap a firm tug is essential to confirm it has locked as securely as the little audible click suggests. It opens instantly with a pull on the red textile tag on the latch. This all happens with your gloves on.

The logo helmet bag has an elastic opening instead of the usual drawstring. Some owners may not like that it does not completely enclose the helmet, particularly if they travel with it. The Mach III Carbon model came with a luggage-quality, zippered carrying bag. That bag is sold separately by 509 for $30.

The rear view reveals the trio of red reflectors, the crown air exhaust vents, and the spoiler.

The owner’s manual seems to be missing some basic user information on several operation items. It’s also hard to read—tiny print! For example, the diagram on how to use the Fidlock buckle is difficult to see and interpret.

Instructions on how to change the shield are a little sketchy. Having done shield changes many times, I could work it out quickly, but new riders unfamiliar with hinge systems may have difficulty initially. Switching to the optional Fire Mirror shield presented an unusual problem not addressed in the 509 Mach V Carbon motorcycle helmet manual.

Because of the shield’s design, the breath deflector is mounted on the shield, not the chin bar. The optional Fire Mirror shield does not come with a breath deflector, so if you want one, you’ll have to remove it from the standard clear shield and attach it to the optional shield or purchase one from 509 for $10.

The screws securing the breath deflector are tiny and blunt-end. The mount point holes on the optional shield do not appear to be threaded, so getting the standard screws to start proved difficult. I got it done by substituting self-tapping screws. Presumably, the optional breath deflector will include the correct size and type of screws to attach it to the shield. The best solution is for the optional shields to come with a breath deflector attached. While riding without the breath deflector is possible, it is less than optimal.

References to avoiding frostbite make me wonder if the manual was produced using a snow helmet manual as the basis, as it seems to only have a vague connection to the features and operation of the Mach V product.

There is quite a bit of content about general helmet do-and-don’t items, though not really much that is direct how-to information on this specific helmet. Also, there is no online how-to content yet. It’s early days for the new 509 street line-up, and this is an item for improvement.

The 509 Mach V Carbon full-face motorcycle helmet is an advanced technology product with room for improvement in the manual and optional items departments. Light weight, dual safety certification, venturi effect ventilation, convenient magnetic chin strap buckle, and slick styling make the 509 Mach V Carbon helmet an all-around value.

509 Mach V Carbon Helmet Specs

Sizes: S – XXL (55-56cm to 63-64cm)

Weight (size XL): 3.84 pounds

Shell: carbon fiber

Certifications: DOT FMVSS 218 and ECE 22.06

Faceshields: Clear, and four tinted/mirror options. No internal sun visor.

Ventilation: Dual closable side-mounted venturi inlets, closable crown vent, and non-closable outlet vents

Retention system: Fidlock magnetic chinstrap buckle

Colors: Blacktop; Burner Red

509 Mach V Carbon Helmet Price: $400 MSRP