The name Deemax reminds me of those legendary yellow wheels from the noughties, but we should really think of it as the Mavic’s gravity division. This new open face helmet fits right in then, with extended coverage around the sides and back to prioritise protection over saving grams and maximising ventilation. That puts it squarely up against some of the best mountain bike helmets around, including the superlative Troy Lee A3.

Deemax is shorthand for gravity, and the new helmet is designed to maximise protection over weight

Mavic Deemax Need to Know

• Gravity-orientated helmet with extra coverage around the back and sides
• MIPS Evolve Core lining to allow for more ventilation
• Comes in three sizes (S-L) and three colours (Grey/Black, White/Black, Olive/Blac)

Design and specification

The latest Deemax MIPS lid has a much more angular and edgy shape than its rounded predecessor and harks back to classic and popular Mavic open faces of the 2010s. Its larger shape and extra features add around 80g of weight over the (very lightweight) previous generation.

Like many rivals, Mavic has opted for the popular MIPS rotational protection system, which uses a plastic slip-plane liner inside to allow the outer shell to rotate a fraction in a crash. The extra movement on impact can help reduce angular forces and jolts to the head and neck and in theory reduce the potential for brain injuries by absorbing some impact energy.

Those three horizontal vents are ideally placed to suck in cool air and dump it right on your brow

The MIPS liner here is the Evolve Core, which means it’s better ventilated than previous MIPS designs, and on the Deemax is set inside a chunky polycarbonate shell with huge vents all over. There’s also a vent strip on the brow that pumps cooling air on the area you need it where blood runs close to the skin at the temples and forehead. 

The inside is reasonably scooped out so the lid sits deeply down on the skull, but not quite so much as a Troy Lee A3 lid or POC Kortal helmet. There’s an insect resistant mesh at the brow built into the padding and a useful little strip of extra padding on the rear retention wheel that stops any digging in at the back.

Cushty Coolmax padding is decent, but not quite as chunky as you would find on a Troy Lee

Mavic’s rear retention wheel has three height positions, tightens the lid from the back and wraps about three quarters of the way round the helmet rather than a full wrap like some designs. The anti-bacterial padding is reasonably thick and well cushioned and uses antibacterial Coolmax padding.

There’s also Pro Deemax model for £20 more money with a magnetic Fidlock chinstrap clasp and a slightly refined retention band system, but I actually prefer the more minimal, smaller and lighter basic plastic chinstrap buckle here. Mavic uses a slightly quirky loop design around the ears where two thinner hoops (rather than straps) circle each ear, and it’s very unobtrusive and keeps things nice and tidy. The long visor is height adjustable and will swing up enough to allow googles underneath, plus there are also rubberised eyewear slots that keep glasses secure if you prefer those.

I set the retention strap to its lowest position to help the Deemax settle deep on my head

Mavic Deemax MIPS Performance

At 385g, the Deemax is a pretty standard weight for an extended coverage open face. It feels a bit heavier though as the overall shape isn’t as low profile and close-fitting to the head as some lids in a similar size. I also found myself at the lowest setting on the rear tensioning dial yet wouldn’t have minded the Deemax sitting even lower down on my head; this also might have helped with the sensation of it feeling a fraction perched on top.

Instead of standard rubbery nylon straps, Mavic has these big, rubbery ear loops: I am a big fan

All the adjustment dials and straps are good quality and I’m a fan of Mavic’s fixed ear loops and minimal chin clasp that never give you that flappy effect of long straps around the sides of the ears that don’t sit quite right. The rear tensioning dial never wiggled loose while riding either.

Despite all the vents, the Deemax isn’t quite as cooling or ventilated as two helmets I use a lot, the Specialized Ambush 2 and Giro Manifest Spherical, and there’s also less of an invisible feel on the head than either of those lids.

Helmet fit is obviously very personal, but despite the generally cushy and comfy padding I had a slight issue in how the Deemax connected with several points on the skull, specifically it didn’t envelop it evenly. I also started to feel slight pressure points on either side of my forehead on longer rides and these could be seen as red patches on the skin after removing the helmet, which I’ve not had with Mavic lids previously.

The Deemax is a solid helmet, but without a 360° it puts uneven pressure on my head