Best Gravel Cycling Helmet: Specialized Prevail II Vent Review

Have a mind to get out on some gravel this summer? Put a lid on it. Our choice for the best gravel cycling helmet is another gem from Specialized.

My happy place is a remote dusty road that climbs out of Idaho’s Long Valley toward our local alpine playground in McCall. It’s about a 100-mile ride from my front door.

I avoid the glutted highway clogged with bumper-to-bumper summer traffic. Instead, I weave a series of backcountry roads over and down mountain passes, pedaling along remote cattle ranches before I pop out at my favorite bar.

My bike and kit may change from ride to ride. But the one constant? It’s my helmet. Lately, I’ve been reaching for Specialized’s Prevail II Vent.

In short: Specialized’s Prevail II Vent ($250) is a light, airy lid that tells my family in real time where I’m at. And if I ever get in a crash, it can share my coordinates with emergency responders when I’m not able to do that myself.


S-Works Prevail II Vent With ANGi

  • Shell: Carbon
  • Protection: MIPS SL
  • Virginia Tech Helmet Rating: 5 stars (11.8, putting it in the top 20 for road cycling helmets)
  • Weight (on our scales): 274 g (9.6 oz.)
  • Price: $250

Specialized S-Works Prevail II Vent (With ANGi) Helmet Review

Unlike most S-Works-branded gear, this helmet doesn’t require a second mortgage. The Prevail II Vent sits at the upper middle of the pack price at $250.

The strap position clears the ears with plenty of room. Because the straps drop near the outside of the helmet, you’ll need to put your sunglasses under the straps.

Fit and Comfort

A helmet’s primary goal is to protect your head. But the price of entry into safety always starts with a comfortable fit. Safety be damned. Who wants to slow-cook a migraine over your ride? We don’t. And Specialized doesn’t believe you do, either.

The Prevail II Vent is a low-profile helmet that snugs securely around the head. The suite of sizes (small, medium, and large) can fit head diameters measuring 51-63 cm. It’s the widest fit range Specialized offers.

The occipital strap (which wraps behind the back of your head) has five different settings, allowing you to fine-tune the forward and aft tilt over the brow. A dial clicks the band to tighten it around the head’s diameter. The dial is easy to click with one hand and doesn’t slip over the duration of the ride.

Dropping spaciously off the helmet and around the ears, thin single webbed straps are bonded to a poly Y joint and clip together under the chin with a plastic buckle.

While many helmets weave adjustable double straps to secure the helmet, we love the simplicity of the single web strap design. There’s plenty of room around the ears, it doesn’t slip, and it’s easy to adjust with one hand on the fly.

Shell and Vents

You can see three toothpick-size stays that bridge the central vent. Specialized replaced seven bridges with these stays.

The major update in this year’s Prevail II is the vent system. Specialized removed seven bulky cross bridges, which stabilize between vents on most every helmet on the market, from the three main air channels and replaced them with seven toothpick-thin carbon rods.

The result is a helmet that looks and feels more open. And by the numbers, Specialized claims it increases airflow by 18%.

In the saddle, the helmet feels pretty breezy. We’ve already logged hot miles climbing upward of 100 degrees F. While it’s never fun to wear a helmet in the heat, the Prevail II does feel notably cool. Plus, my hair remains dry in the exposed channels.

To manage sweat, Specialized’s padded Gutter Action System moves sweat away from your eyes and off of the pads over the temples.


MIPS sits underside the pads that line the helmet. If you crash, those little straps allow the pads to shift 10-15 mm. You get the same protection but at a fraction of the weight of other MIPS helmets.

In addition to the minimal venting, the Prevail II lightened the protection with a new super-light MIPS SL (multidirectional impact protection system).

MIPS is a third-party polymer insert that buffers angular impacts often associated with bike crashes. The technology is licensed out to companies and sits between the helmet’s foam and the head.

On the Prevail, it actually sits on the underside of the foam padding, tethered with watchband keepers.

Flip the helmet over and you can push the padding around and see the 360 degrees of directional play. It offers the same brain protection benefits as other versions of MIPS and received a five-star rating from Virginia Tech’s Helmet Ratings.

Listed under Specialized’s road helmet lineup, this gravel-centric helmet has more coverage around the back of the head than most pure road helmets. A lot of all-road helmets have this, but Specialized integrated four vents in the lower portion and drops four exhaust vents out back into the bottom to help flow heat away from the head.

The deep vents are capped with thin carbon strips. This keeps the weight down and the protection where you need it — on potential high-contact points.

ANGi Sensor for Emergency Response


Want to tell friends and family where you are? Want emergency help when you can’t do it yourself? Specialized made a move to add its ANGi (Angular and G-Force indicator) Crash Sensor to all of its helmets. The device sits adjacent to the occipital dial on the Prevail II and pairs with Specialized’s Ride app through your phone.

The benefits are threefold. Friends and family can follow you on your ride, and the device has an accelerometer that can sense what kind of impact you might have had (including angular impact forces). And in the event you can’t reach your phone, it will send an alert to friends, family, or emergency responders for help, sharing your specific coordinates.

The registration is pretty simple. You download Specialized’s Ride app, create an account, and the ANGi syncs to your device via Bluetooth.

Sure, I can share my location with my existing phone through the Find My Phone app. But it can’t make a call for me if I’m flat out on the ground. And this is where the ANGi sensor comes in handy.

If the accelerometer senses an impact, it connects to the Ride App on your smartphone, sounds an alarm, and starts a countdown. Just a bump in the road? Cancel the countdown and keep riding.

If you are injured or unconscious and can’t cancel the countdown, the Ride App will send a text alert to your emergency contacts, telling them you may have been in an accident.

Attached to the helmet and not the bike, the sensor tracks impact directly to your head, minimizing any sloppy data sharing tied to a bump with the bike.

I tend to ride solo, and the ANGi brings peace of mind to my family. They can follow me along on my ride, I can show them where I’m at when I’m running late, and if I can’t do it myself, it tells them I’ve been in an accident.

Three screenshots from the Ride App using the ANGi Sensor. Left, my route. Middle, a summary of my route. Right, what my emergency contact sees when they check in on my route. The app leaves breadcrumb waypoints to share my latest coordinates from the ride.

Again, the best helmet is the helmet that fits. All helmets sold in the U.S. will meet the federal Consumer Product Safety Commission (CPSC) ratings. If the Prevail doesn’t fit your head, you can still buy the ANGi sensor ($50) and mount it to a helmet that does fit.

Shop S-Works Prevail II Vent Helmet

Steve Graepel

Steve Graepel is a Contributing Editor and Gear Tester at GearJunkie. He has been writing about trail running, camping, skiing, and general dirtbagging for 10+ years. When not testing gear with GearJunkie, he is a Senior Medical Illustrator on the Neurosurgery Team at Mayo Clinic. Based in Boise, Idaho, Graepel is an avid trail runner, camper, angler, cyclist, skier, and loves to introduce his children to the Idaho outdoors.