Troy Lee Designs Grail review – the brand's first ‘any bike’ helmet for riders who want MTB-style protection without a peak

Troy Lee are impact protection icons in mountain bike and motocross and now they've pulled the peak off their popular Flowline MTB helmet to make a multipurpose lifestyle lid

Troy Lee Grail helmet
(Image: © GuyKesTV)

Bike Perfect Verdict

Chunky MIPS protection and MTB-style deep dish coverage make the Grail a solid, gravel/adventure/commuting option. It’s big and bulky though and no cheaper than the peaked Flowline version.

Pros

  • +

    ‘Deep Dish’ back of head coverage

  • +

    Five-star Virginia Tech and e–Bike safety rating

  • +

    Excellent universally stable fit

  • +

    MIPS ‘slip-plane’ protection

  • +

    Troy Lee Design trail kudos

Cons

  • -

    Bulky

  • -

    Adequate not amazing ventilation

  • -

    Peaked Flowline is same price

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Troy Lee Designs make some of the best mountain bike helmets and has built a super loyal following for their excellent fit, style and protection over the past thirty years. Now those strengths are available in an ‘any ride’ style via the peakless Grail helmet, but the MTB-derived design means it’s not as sleek or well-vented as road-derived lids. 

Design and build

Troy Lee Design’s claim that “The Grail Helmet breaks the mold” seems at best ironic as it seems to use exactly the same mold as the Flowline MTB helmet, just without a detachable peak.

That means it’s distinctively chunky compared to most gravel/adventure helmets and it drops further down towards the nape of your neck too. The 14 trapezoidal vents in the angular shell leave the sides largely solid too. There are twin ‘eyebrow’ scoops and some shallow internal channels add through flow to the rear exhaust vents though.

A dial controls the circumference of the fit cradle, which also has three height settings. The extensive padding sits on the rubber-mounted MIPS cradle designed to reduce deceleration damage of the brain inside your skull. The Grail has the same NTA 8776 e–Bike certification and 5-star Virginia Tech independent safety test rating as the Flowline too.

Troy Lee Grail helmet

Deep dish back, extra side and front projection plus unvented sides mean extra protection for rougher, wilder rides (Image credit: GuyKesTV)

Performance

Extra protection is undoubtedly the big win with the Grail too. Not only does it extend coverage down your neck behind your ears but it projects further out over them sideways and out over your brow too. The front of the helmet sits very low too, actually acting as a mini peak to keep high sun and hard rain out of your eyes. The solid sides mean less chance of a branch poking your head on singletrack or a rock contacting your skull if you crash. 

Troy Lee’s signature rounded fit seems as universally comfortable as usual and the cradle is super secure with no pressure hot spots even on long days. The fact the Grail isn’t very holey and has limited internal airflow means overall temperatures inside are high. That’s obviously welcome on cold days and I was comfy in the Troy Lee on days I’d have worn a cap under other helmets. It’ll boil your bonce much earlier on warmer days though, so if you’re lucky enough to have them regularly you’ll want a better vented lid.

Troy Lee Grail helmet viewed from the top

The Grail isn't that Holey and cooling ventilation is limited as a result (Image credit: GuyKesTV)

Verdict

If I had to pick a peak less XC/gravel/all road helmet to crash in, the MTB derived  Troy Lee Grail would probably be top of my list. Not only does it’s MIPS suspended design exceed e–bike use standards, but the chunky design physically keeps your face, ears and neck further off the ground if you slam and slide.

That makes it bulkier and hotter to wear than other more road-derived designs though and it seems cheeky that removing the peak from the Flowline helmet doesn’t remove any of the cost.

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The lowdown: Troy Lee Designs Grail helmet
AttributesNotesRating
ProtectionSuspended MIPS and good all-round coverage★★★★
ComfortGreat on colder days, will run warm on hotter★★★
Value for moneyMiddle of the road price for what you get★★★

Troy Lee Grail helmet from behind

MIPS literally adds another layer of protection and Troy Lee Designs internal shape and fit seems to work really well for most riders (Image credit: GuyKesTV)

Tech specs: Troy Lee Designs Grail 

  • Price: $109.99 £99.99 €119.99
  • Sizes: XS/S, M/L (tested), XL/XXL
  • Options: Forest Green (tested) White, Black and Red
  • Weight: 290g (M/L)
Guy Kesteven
Technical-Editor-at-Large

Guy Kesteven has been working on Bike Perfect since its 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. He’s also penned a handful of bike-related books and he reviews MTBs over on YouTube.

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

Height: 180cm

Weight: 69kg

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