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BTwin 500 Bike Helmet



Remarkably competent helmet for commuting, touring and light trail duties – an absolute bargain

At every product is thoroughly tested for as long as it takes to get a proper insight into how well it works. Our reviewers are experienced cyclists that we trust to be objective. While we strive to ensure that opinions expressed are backed up by facts, reviews are by their nature an informed opinion, not a definitive verdict. We don't intentionally try to break anything (except locks) but we do try to look for weak points in any design. The overall score is not just an average of the other scores: it reflects both a product's function and value – with value determined by how a product compares with items of similar spec, quality, and price.

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The BTwin 500 bike helmet is apparently designed for general riding and reckoned capable both on and off road. Usually this best of both worlds premise results in disappointment and, true, there are some minor compromises, but at £17 it's an absolute bargain.

Like most lids these days, it complies with EN1078 and follows the in-mould construction (where shell and EPS liner are formed together simultaneously). Build quality is extremely high, superior to many I've tested commanding nearer £100.

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Though not everyone's bag, the fluoro yellow polycarbonate shell is particularly well finished and extends around the rim, protecting the EPS liner from the inevitable, everyday carelessness that comes with general riding.

BTwin 500 Bike Helmet - inside.jpg

There's a relatively shallow peak up front, which lacks the porch-like protection of trail-specific designs but doesn't look out of place when you're riding a cross/gravel or touring bike.

BTwin 500 Bike Helmet - side.jpg

Having 21 vents isn't really a talking point these days, but they are well designed and give decent levels of ventilation. 3D fit is another concept we've come to take for granted; it's intended to behave like a roll-cage, protecting the brain from twisting forces experienced in a crash.

The familiar thumbwheel system is intuitive and the Y and chin straps feel surprisingly tactile against the skin – even for long periods. On paper, two sizes might dent widespread appeal, though the medium (53-59cm) caters for most adults and, retrospectively, would have been a better choice than the 59cm on test.

BTwin 500 Bike Helmet - back.jpg

Nonetheless, substituting the pads supplied for a compatible set in my bodge box, and 60 seconds later, fit was dialled to perfection. I'm not sure whether size has any bearing on this, but coming from my angular road lids, I was quite conscious of the dome-like profile for the first few rides. I soon forgot about it though.

The first hundred miles of testing were done on my TT-inspired fixer and at 20mph plus. Admittedly, mid-late April and early May felt like a typical first week in March, but even in these contexts and with a thick thatch (it's not me in the photos!), airflow certainly kept pace.

At the other extreme, winching up 1 in 7s on an 81-inch fixed gear, or trundling home on my Univega with a week's shopping in tow didn't induce a soggy scalp.

On fast descents, noise was minimal, so unless the wind is really raging, maintaining conversation should prove pretty easy.

> Check out our guide to the best cheap helmets

Touring and commuting are its obvious strengths, and although not a trail lid in the proper sense, its sturdy construction and moderate peak lend themselves nicely to forest fun, giving reasonable protection from low hanging branches and brambles.

Damp cloth once-overs are generally enough to keep it looking sharp, although some mucky rides on the wild side saw it join me in the shower afterwards.

Ultimately, there are better choices for road purists, but standards of comfort and performance for general or even spirited riding are impressive – if it fits, why pay more?


Remarkably competent helmet for commuting, touring and light trail duties – an absolute bargain

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Make and model: BTwin 500 Bike Helmet

Size tested: Large, 59cm-61cm

Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?

Decathlon says: "Protecting on and off-road cyclists' heads.

"Sporty design: 21 vents provide excellent ventilation. The 3D dial-fit adjustment provides great comfort and a secure, snug fit."

Remarkably capable helmet for commuting, touring and light trail riding.

Tell us some more about the technical aspects of the product?

Decathlon lists these features:

21 vents.

LIGHTWEIGHT 270 g in size M.

EASE OF USE 3D dial-fit adjustment for height and circumference.




M (53-59 cm); L (59-61 cm).


Neon yellow.

Black, orange and grey

Rate the product for quality of construction:

Really well finished.

Rate the product for performance:
Rate the product for durability:

Has shrugged at the usual everyday carelessness so far.

Rate the product for weight (if applicable)

Feels lighter than 352g suggests.

Rate the product for comfort (if applicable)

Great fit and excellent airflow.

Rate the product for value:

Phenomenally good given the build quality and overall specification.

Tell us how the product performed overall when used for its designed purpose

Overall, the BTwin 500 is a remarkably capable best-of-most-worlds design ideally suited to commuting, touring and light trail riding. Good ventilation and moderate weight ensure that it's comfortable over long distances and higher speeds. Superb build quality means it will shrug off everyday carelessness and, given the design brief, its hard to see why you'd pay more.

Tell us what you particularly liked about the product

Pretty much everything.

Tell us what you particularly disliked about the product

Nothing, although the peak was perhaps a little on the shallow side for trail work.

Did you enjoy using the product? Yes

Would you consider buying the product? For general riding, absolutely.

Would you recommend the product to a friend? Yes, an absolute bargain if they wanted a versatile lid with a commuting/touring bias.

Use this box to explain your score

Phenomenally good helmet for the money, but when everything is taken into account, 8 better reflects overall performance.

Overall rating: 8/10

About the tester

Age: 42  Height: 1m 81  Weight: 70kg

I usually ride: Rough stuff tourer based around 4130 Univega mountain bike frameset  My best bike is: 1955 Holdsworth Road Path and several others including cross & traditional road

I've been riding for: Over 20 years  I ride: Most days  I would class myself as: Experienced

I regularly do the following types of riding: cyclo-cross, commuting, touring, fixed/singlespeed, mountain biking

Shaun Audane is a freelance writer/product tester with over twenty-eight years riding experience, the last twelve (120,000 miles) spent putting bikes and kit through their paces for a variety of publications. Previous generations of his family worked at manufacturing's sharp end, thus Shaun can weld, has a sound understanding of frame building practice and a preference for steel or titanium framesets.
Citing Richard Ballantine and an Au pair as his earliest cycling influences, he is presently writing a cycling book with particular focus upon women, families and disabled audiences (Having been a registered care manager and coached children at Herne Hill Velodrome in earlier careers)

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