MC Tested: Arai Signet-X And Quantum-X Helmet Review

New full-face motorcycle helmets are intended to please long- and round-oval head shapes.

Arai helmet review
Journalists were invited to test the new Arai Signet-X and Quantum-X back-to-back on a two-day street ride in Southern California.Photo: Drew Ruiz

Protection is job one for a helmet. Case in point: Josh Day was wearing Arai's top-of-the-line Corsair-X last June during MotoAmerica Superbike practice at Road America when he was spectacularly catapulted from his Yamalube/Westby Racing Yamaha YZF-R1.

Day landed heavily, head and body skipping across the paved runoff area outside of turn six. The 27-year-old Floridian was rushed by ambulance to a local hospital and, later, a nearby trauma center, where he was diagnosed with a brain injury and a broken wrist. In the months since the accident—his third big crash of the season—Day has made steady progress. “I feel completely normal,” he told me. “Nothing is really bothering me. It will still take more time. We’re letting my head work through its cycle, taking it day by day.”

Day’s fall was used as a dramatic example at the recent press introduction of the new Signet-X and Quantum-X, which are derived from the Corsair-X introduced last year and share many of its features and qualities, despite a significantly lower price point. “Touring riders may not travel as fast as racers do,” Arai CEO Michio Arai said in a taped event greeting, “but protection of the level seen with the Corsair-X is just as valuable to riders on the highway.”

Arai Signet X front
Round vs. long: Competition continues to influence product development. “We learned through racing that Americans have differently shaped heads,” said Arai’s Brian Weston.Photo: Arai
Arai Quantum-X
Like the Signet-X, the Quantum-X is manufactured entirely in Japan. Arai doesn’t source any parts from other countries except for the drawstring bag in which the helmet is delivered.Photo: Arai

Next-Generation Design

Like the Corsair-X, basis for the “long-oval” Signet-X and “round-oval” Quantum-X is a smooth, round fiberglass shell designed to glance off objects, which, according to Arai Managing Director Brian Weston, “is just as important as energy absorption.”

Making an Arai helmet
According to Arai, the three most important components of a helmet are the shell, EPS liner, and chinstrap. Three people at the factory in Japan are certified to install chinstraps.Photo: Arai

Another claimed benefit of a smooth, round shell—created using what Arai calls Peripherally Belted Super Complex Laminate Construction—is that the helmet is more aerodynamic and quiet even when the wearer turns his or her head at high speeds.

That shell doesn’t incorporate a lightweight, expensive material known as Zylon, which is reserved for the Corsair-X. The Signet-X and Quantum-X further differ from the Corsair-X in that they uses three, rather than four (of a possible 10), EPS liner densities.

Arai helmnet liner
One of the differences between the Signet-X and Quantum-X is the positioning and thickness of the padding used for the removable, adjustable, and washable interiors.Photo: Arai

Both the Signet-X and Quantum-X employ the Variable Axis System (VAS) faceshield that debuted on the Corsair-X. This design lowers the operating mechanism, increasing the area above the side pods for a rounder, smoother surface along the Snell test line.

Incoming air travels through the same internal paths between the shell and liner as the Corsair-X, albeit with two fewer openings. Sliding QVF crown intake and three-position QVR back-of-helmet exhaust ducts are also shaped and operate differently.

Signet-X helmet
Quantum-X and Signet-X (shown here) evolved from the Corsair-X. “Arai is like an orchestra,” said Arai CEO Michio Arai. “R&D is writing the music, and the other departments are playing it.”Photo: Arai

On My Head

Journalists were invited to test the Signet-X and Quantum-X back-to-back in Southern California. Racers Jake Zemke and Steve Rapp led the mostly two-lane route, which began in Venice, overnighted in Paso Robles, and returned to Venice by a different way.

A representative from Arai measured my head and concluded that the best choice for me would be a long-oval Signet-X in size Medium. I spent the first day in a Signet-X and the second in a Quantum-X, albeit with a Corsair-X interior to create an “intermediate-oval” fit.

Both helmets fit me well, although I found the Signet-X more comfortable. The vents are easy to open and close with gloved hands, and I could actually feel air moving through the helmet, which was a blessing in Taft, where it was 111 degrees Fahrenheit.

I’ve been wearing a Corsair-X for more than a year, so changing shields is now second nature. “The new shield system is more intuitive and easier to use,” Weston said. “That may overshadow the fact that this is a better helmet.”

Based on my two-day ride, as well as consistent use during the weeks since the event, the Signet-X and Quantum-X represent a step forward for Arai in comfort, features, and protection at a price point that is within reach of a greater number of motorcyclists.

Six Ways In Which The Signet-X And Quantum-X Are Identical:

  1. Peripherally belted, Super Complex Laminate Construction (PB­ScLc) shell design
  2. QVF and QVR upper ventilation ducts
  3. Anti­microbial Eco-Pure liner materials
  4. Variable Axis System (VAS) faceshield system
  5. XS­-XXL sizing
  6. Pricing ($679.95 to $839.95)

Four Ways In Which The Signet-X And Quantum-X Differ:

  1. Signet-X EPS liner is longer front to back and narrower side to side for heads with pronounced length but reduced width; the removable multi-piece Eco-Pure liner is identical to that of the Corsair-X.
  2. Quantum-X EPS liner is shorter front to back and wider side to side for riders with an even balance between length and width; the removable multi-piece Eco-Pure liner has thicker front and rear padding (installing a Corsair-X liner provides an "intermediate oval" fit).
  3. Signet-X is available in seven solid colors and one graphic in three colors; Quantum-X is offered in seven solid colors and one graphic in four colors (more graphics for both models are expected next summer).
  4. Chin bar and vent styling are slightly different for no reason other than to make differentiating between the two models easier.