Giro Tyrant helmet review

The Giro Tyrant brings excellent, innovative and extended protection without being a head oven

Giro Tyrant helmet
(Image: © Guy Kesteven)

Bike Perfect Verdict

Giro’s Tyrant gives significant extra crash protection with remarkably little heat or hearing compromise and comparatively low cost to smash the open face aggro helmet benchmark out of the bike park


  • +

    Excellent spherical MIPS protection

  • +

    Extended over-ear coverage

  • +

    Far better venting and hearing than you’d expect

  • +

    Reasonable price for tech


  • -

    Will still get hot on long climbs

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 When Giro launched their innovative ‘spherical MIPS’ Aether helmet a couple of years ago an MTB version was already being designed behind closed doors when we visited their Santa Cruz HQ. They’ve used all their vast experience from 30 years of helmet making to take that tech, add ear protection coverage and still keep the Tyrant wearable when it’s warm. Add a surprisingly affordable cost and it’s one of the few lids that everyone we know who’s used it loves and a definite new benchmark for open face helmet design.  


Spherical MIPS works by using two completely separate inner and outer helmets connected by flexible MIPS tethers. That lets the outer helmet ‘roll’ independently on impact like a ball and socket joint, dramatically reducing energy transfer to your brain. The Tyrant takes this exclusive Giro tech further by using a high-speed impact damping EPS foam in the outer and an EPP inner segment that sucks up low-speed impacts better. The inner section also gets a particularly secure DH version of the AirLoc fit cradle with chunky sawtooth adjustment dial and 3D formed occipital pad. The outer inner (if you see what we mean) also gets a separate hardbody shell around it’s lower rim to increase protection, which is a feature borrowed from Giro’s snow helmets. The outer hardshell then extends right down below your ears.

Short, simple straps dangle from the lower shell tips with a long adjustable visor that tilts from just in eye line to ‘high enough for goggle storage’. Nine medium-sized vents in the outer section are matched with corresponding vents in the inner section (there are two more over each ear). The pads sit on slightly raised lumps to boost air circulation over the whole head with some deeper vents in key places. ‘Stack’ vents on the brow are specifically designed to pull air upwards and help de-fog goggles too.   


With so much going on you could almost forgive the Tyrant a slightly awkward fit as is the case with many deep-dish helmets. Apart from the extended shell twanging off your ears on the way in though the fit is fantastic straight away. The big padded cradle holds it super secure with even light tension so the chin strap is almost a formality. Every tester who tried it said the same too, which is super rare given the variety of head shapes we have on the team. There’s no obvious extra wobble, creak or rattle from the twin shell design either. There’s enough space between the over-ear sections and your actual lugs to cut down wind noise enough for a calming ‘zen’ effect but shouted warnings or sharings of stoke from other riders still come through loud and clear. 

What really surprised us is how effective the cooling is from just a few vents. The temple vents in particular pipe air straight onto your skull and then it sheets over your entire head rather than getting trapped or just pulled through specific vents. It’s certainly not the best venting helmet we’ve used in the extra protection category (Lazer’s convertible Revolution still takes that breezy crown by a long way but it’s cool enough to stay on your head for the climb back up or when you’re charging along singletrack in your lightest shirt and shorts. 

At just over 600g it’s lighter most extended protection helmets and while we’ve not tested the full spherical MIPS impact resistance we’ve had enough slide outs and branch swipes to be glad of the anti Van Gogh protection several times over.

It’s around half the price of the Spherical MIPS loaded Giro Aether road lid and the detachable chin guard, conventional MIPS Giro Switchblade too so in comparative terms it's excellent value.

Giro Tyrant helmet

Don't be discouraged by the lack of vents, the Tyrant still manages to keep your head cool enough on long climbs (Image credit: Guy Kesteven)


It’s rare - in fact, this is probably the first time ever - that everyone in our test team praises a helmet as unanimously as the Tyrant. Obviously it’s not for XC bike rides or hot and fast trail use, but for any situation where extra coverage and impact protection is a good idea, but you don’t want a full face this is an outstanding lid. The fact the extra protection is delivered without roasting your head, killing your hearing or milking the price makes it an absolutely awesome helmet for seriously aggro riders. 

Tech spec:  Giro Tyrant helmet 

  • Sizes: S, M, L
  • Vents: 13
  • Colours: 6
  • Weight: 622g (medium)
  • Price: £134,99
Guy Kesteven

Guy has been working on Bike Perfect since launch in 2019. He started writing and testing for bike mags in 1996. Since then he’s written several million words about several thousand test bikes and a ridiculous amount of riding gear. To make sure he rarely sleeps and to fund his custom tandem habit, he’s also penned a handful of bike-related books and talks to a GoPro for YouTube, too.

Current rides: Cervelo ZFS-5, Specialized Chisel, custom Nicolai enduro tandem, Landescape/Swallow custom gravel tandem

Height: 180cm

Weight: 69kg