Targeting enduro riding and racing, backed up with design input from EWS Champion Richie Rude, Giro’s Insurgent is 200g lighter and a claimed 50% more breathable than the brand’s Disciple downhill helmet. This is despite featuring the highest protection levels and all-new MIPS Spherical Technology, where dual foam layers slide over one another inside the shell.

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This Spherical system (also used by Bell) is best described as layers moving like a ball and socket joint to redirect impact forces. One EPS layer absorbs high-speed impacts, and the other EPP layer is slower-rebounding to better deal with the type of crashes where the ‘rider rolls around in the dirt’. The chinbar also gets an expanded polypropylene filling (that’s often used in vehicle bumpers and trim).

Made from prepreg fibreglass, the Insurgent’s shell is seriously stiff and solid, except for a couple of squidgy ‘bridges’ called Flex Gaskets on the chinbar under the ears. Hard to spot, these are a patent-pending Giro technology designed to reduce collarbone injuries, where the helmet is forced down onto a rider’s shoulder in a crash.

The Insurgent has much smaller vents than most lighter-weight full face lids, and a smaller, mesh-covered chinbar opening, so you might reasonably expect cooling to suffer. There’s definitely a less airy and open feel and less air pumping directly into your mouth than Fox’s Proframe, so cooling is comparatively compromised.

Brow slits are effective on the forehead, but more heat builds up inside and it gets steamy both on the crown of the head and especially around the neck and behind the ears. In part this is due to having by far the most secure, cosy, and locked-down feel to the padding of any helmet on test, and a neck roll that really cradles the back of the head.

We’ve used Giro full face lids for generations and while their fit often feels on the tight side when putting them on, it’s always spot on when actually riding. We settled into the pads and remained supremely comfy all day with no hot spots and good ear clearance. There’s absolutely zero helmet movement too, even if you’re headbanging through braking bumps or landing big drops.

This really solid feel brings a sense of security that makes it easily the most reassuring on test. Unsurprisingly this is reflected in it being the heaviest here (incidentally, our sample was 80g more than claimed). If serious protection is top priority, we all agreed that the Insurgant is the helmet we’d all grab.

This locked-down proper DH helmet vibe is reflected in the motorbike-style D-Loop chinstrap that takes a lot longer to fasten than a magnetic system. It’s a bit of a faff, but acceptable since this is more of a lid for uplifting, serious enduro racing and taking risks than recreational e-biking or trail riding at the bike park. The higher weight and steep asking price also underlines its serious intentions.

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