The Smith Mainline Helmet is a Winner [Review]

Matt reviews the Smith Mainline helmet, a lightweight, enduro-ready full-face mountain bike helmet that's ready to shred.
Smith Mainline Helmet

For having one of the most seen mountain bike helmets on the trails – at least in my anecdotal calculation – Smith has taken their sweet time developing helmet with stronger gravity intentions. Introducing the very first full face in their line up; the Smith Mainline.

Smith’s First Full Face MTB Helmet

The new Smith Mainline helmet has a lightweight in-mold construction with complete Koroyd coverage for a stronger skeletal structure with better ventilation. Smith adds that the MIPS lining reduces rotational forces. MIPS is basically a slip-plane, deflecting the energy from oblique impacts, but Koroyd also helps displace rotational energy, while acting as sort of a crumple zone.

“Designed for the elite level user, Smith’s team of product designers and engineers spent two years developing the pinnacle product with informed insights from notable Rocky Mountain Enduro athletes Remi Gavin, Andreane Lanthier Nadeau, and Jesse Melamed. The Smith-sponsored team was crucial in formulating and refining the construction, design, features and aesthetics of the DH-certified (ASTM F1952) enduro helmet.”

The Smith Mainline MIPS has a total of 21 vents with internal air channels which combine with intake and exhaust ports for optimized ventilation, even when wearing goggles.

The full-face helmet also includes three sets of cheek pads — small, medium, and large — and two sets of crown liners in different sizes. The Mainline helmet uses a D-ring chinstrap fastener and it comes in at a light 800g. All that protection technology in a lightweight package with the Smith name rings in at $300.

Smith Mainline MIPS Helmet On the Trail

 Smith Mainline Helmet
A little more confidence for bigger features. Photo: Hannah Morvay

I have yet to make it to a bike park this season. Only one in my more immediate area is actually open at the moment, and I have been spending more of my time on backcountry rides, since the one bike park that has been open looks like it’s been slammed with people.

I rarely ever ride singletrack with a full face mountain bike helmet, but with some gnarlier, bike-optimized riding available close to home at Floyd Hill, I took the Smith Mainline there, strapped up, and started climbing.

The visor has about a half-inch of travel, clamped into place with a turn dial.

And, I was impressed. I swung these Smith Squad XL MTB goggles around to the back with the strap on the brow of the helmet, and I wasn’t more bothered than I would have been climbing with a half-shell. That’s not to say that it’s not going to get more hot than a half-shell, especially on warmer days on an exposed trail. Light breezes can be felt through the helmet’s intake vents.

Smith Mainline Helmet
It might take a little bit of target practice, but it’s not impossible to to quench your thirst with the helmet on. Photo: Hannah Morvay

The Smith Mainline is an Enduro Helmet

Smith classifies the Mainline as an enduro helmet, and with the Rocky Mountain Race Face enduro crew marketing the full-face helmet, it likely means that a lot of other enduro riders will also be wearing it uphill, and eventually, they’ll get thirsty. The large, open vent in the front of the chin bar makes it easier to get a hydration tube through, or squirt a bottle into.

Once you’re pointed downhill, the Mainline helmet is forgettable. There’s an added confidence from the ASTM F1952 DH-certification, and with more wind flow, my sweaty head began to dry out quickly.

The cheek pads that came in the helmet were a little too tight for me, but since there are two other sets included, I swapped to a thinner set, and they worked great.

I also tested the Smith Squad XL ChromaPop goggles. The lenses have a red tint, which reduced highlights and bright spots on the trail, making greens very vivid. The Squad XLs gave me a clear advantage when it came to recognizing terrain, and they were lightweight and fairly well vented.

Review Conclusion: A Lightweight and Serious Full Face MTB Helmet

Smith Mainline Helmet
Photo: Hannah Morvay

The Smith Mainline full-face helmet is light, breathable, and it looks great. The DH-certification and D-ring buckle add to the Mainline’s ruggedness, while the Koroyd-lined interior makes it easy to wear. Smith fans have long been waiting for a more serious mountain bike helmet, and this offering shouldn’t disappoint.

Check out our mountain bike helmet buyers guide and our picks for the best mountain bike helmets.