Troy Lee Designs Flowline 2023 helmet review – two new TLD trail lids

Troy Lee Designs new Flowline helmets drop the moto graphics but gain extra safety tech and more affordable price tags. We’ve been riding both of them

Troy Lee Designs Flowline hero shot
(Image: © GuyKesTV)

Bike Perfect Verdict

Typically super comfortable, high protection helmet from Troy Lee with basic and fancy (SE) options and loads of size and color choices. They run hotter than most though.


  • +

    Excellent multi-size fit

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    Five Star protection rating

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    Fancy (SE) and functional options

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    Loads of colors

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    Competitive pricing


  • -

    Runs hot

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The legendary fit of Troy Lee Designs has always put them in our best mountain bike helmet lineup. The new Flowline and Flowline SE keep that favorite fit with a five-star Virginia Tech testing score and a vast range of colors. Basic (Flowline) or fancy feature (Flowline SE) options give reasonable and achievable pricing levels. Excellent initial comfort is offset by less impressive ventilation and heat management if you're pedaling not just plummeting.

Troy Lee Designs Flowline SE on riders head

Both Flowline helmets use the same basic design with extra eyebrow vents and 'peaked' three-position visor upfront (Image credit: GuyKesTV)


Both helmets use the same upper and lower outer hardshell with a broad central beam and 14 vents. These include long ‘eyebrow’ slots to augment flow from the four big front vents and help keep glasses clear and five exhaust vents at the rear. The center, rear top, and sides of the helmet are solid so you’re relying on internal channels on the far side of the MIPS ‘slip plane’ sheet for cooling your scalp. 

The peak clicks through three positions depending on your fashion/protection needs. The straps sprout from the inside rather than the edge and the TLD logo ratchet wheel tightened fit cradle is also height adjustable. 

Back of Troy Lee Flowline helmet

and six exhaust vents, extended coverage, and adjuster dial at the rear (Image credit: GuyKesTV)

Flowline versus Flowline SE

While both helmets use the same overall design and MIPS sheet, it’s the usual yellow on the Flowline but a stealthy black on the Flowline SE. The multiple pad layout uses basic ‘sausages’ on the Flowline but slimmer sealed edge (think toasted sandwich) microbial pads on the SE. The SE also gets a fancy TLF logo Fidlock magnetic strap for instant connection compared to the standard snap-lock buckle on the Flowline. What you can’t see is that the SE also gets dual-density material, while the Flowline uses the same foam throughout.

Different helmet buckles

Different buckles are the most obvious difference between the two Flowlines in use but the SE should smell fresher for longer (Image credit: GuyKesTV)


Interestingly while both helmets get a top five-star safety rating from the independent Virginia Tech test labs the single-density Flowline actually gets the better score. They both pass all relevant CPSC, CE, and E-bike use certifications too. Three different sizes help refine fit and the comfort and security that’s given TLD lids a massive fan base is fully evident on the Flowlines. The cradle stabilizes without any obvious pressure points and doesn’t even shift around when you’re running a helmet light. The MIPS liner doesn’t creak and the weight is average for similar-priced/protective helmets so in terms of wearing it basically just vanishes into the background in a really good way.

The distinctive peaked visor shifts from just about visible in the eye line for extra sun/rain protection to high enough to sit glasses underneath, how well they slot into vents depends on the arm design though. The visor doesn’t flop up or down and both helmets have a really good quality, solid build feel about them. The relatively high area MIPS layer and lack of mid-section vents meant I was getting hot with a bald head even in single-digit temperatures on stop/start rides. That's likely to translate into serious sweating on harder climbs in warmer weather which impacts its all-rounder rather than gravity appeal.

Inside of both Flowline helmets

MIPS color and pad style make it easy to tell between the Flowline (left) and Flowline SE (right) from the inside  (Image credit: GuyKesTV)


Both Flowlines fit great, continuing Troy Lee’s reputation for benchmark comfort and they come in loads of colors and offer excellent protection too. That makes the fancier pads and ‘magic’ magnetic buckle the practical difference between the Flowline and SE in use, so you’ll have to decide if that’s worth the $40 / £40 upcharge. 

There are loads of really comfortable, high-protection affordable helmets around now though which makes the lack of cooling more of a comparative issue for all-round riders. It’s also worth noting that the classic A1 helmet with MIPS (and more vents across the top) is half-price ($87 / £65) in Troy Lee Design’s own sale and elsewhere while stocks last.

Tech specs: Troy Lee Designs Flowline and Flowline SE

  • Price: Flowline $119 / £100, Flowline SE $159 / £140
  • Sizes: XS/S, M/L, XL/XXL
  • Options: White (SE in pictures, Dark blue (Flowline in pictures), Oasis blue/black, Magenta/black, Gold/black, Black, Gray, Forest green, Cinnamon (brown), Apple (red), and Mirage blue.
  • Weight: 360g
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