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B’Twin CO2 Inflator and 16g Cartridge



It's as small as these things get, works intuitively and gives fine control. For eight quid, it's a cracker

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 CO2 Inflator & 16g Cartridge Set is probably the best-value inflator on the market. At £8, fitting 16 or 25g canisters with precisely-controllable one-handed inflation, it's a great buy.

With the head threaded most of the way onto the cartridge it's 12cm long, and easily slips into a pocket. Removed from the cartridge it's as small as these things get, so easily put into a tool roll.

> Find your nearest Decathlon store here

> Buy this online here

It's hard to imagine a simpler process: screw on the canister fully, press onto valve – done. In reality, the pressing down onto the valve will push it through the rim if you've removed the threaded ring from your valve stem, or are running unthreaded valves. Either way, applying pressure opposite onto the tyre to keep the valve in place is dead easy, and as the tube starts to inflate, the valve very quickly resumes its natural position and pushes back against the inflator head.

If you have your thumb against the tyre then it's intuitive to gauge how much CO2 has flowed in – more so, I believe, than more upmarket inflators with on-off knobs, where you are not pressing against the tyre as a matter of course.

The fact that the head is angled is a bonus over those where the cartridge is set at 90 degrees to the valve – you need to push down with a less-aligned force in that instance, making gauging how hard to press and for how long less intuitive.

On the first inflation I managed to get it spot on the 50psi I was aiming for with a 28mm front wheel – the most accurate I've ever managed to be with an inflator, I think. On the second shot at an empty 28mm tyre I managed to get 30psi before it was completely empty – which roughly aligns with the maths on grams-of-CO2-per-psi.

> Check out our guide to the best pumps and CO2 inflators

The metal head is very cold to touch, so I imagine emptying the entire cartridge in one go would be borderline painful if you weren't wearing gloves or using a bit of fabric – a sleeve, snood or casquette maybe. Because you want to have your forefinger and thumb either side of the head to control pressure I'd say such lengths are recommended – you can use it by holding the plastic insulated sleeve, but the control afforded is not as nuanced.

The plastic sleeve and rubber band that slips around the canister is minimalist but does the job, and will take 16 or 20g cartridges.

All in all, for eight quid including a 16g canister, it's a great buy.


It's as small as these things get, works intuitively and gives fine control. For eight quid, it's a cracker test report

Make and model: BTwin CO2 Inflator and 16g Cartridge

Size tested: n/a

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?

It's for Presta or Schrader valve users, looking for a cost-effective, fast solution.

Decathlon says: "This is a great value CO2 inflator for your bike allowing your quickly inflate your tyre. Works with both Schrader and Presta valves. The angled head makes it easy to use and the plastic cover keeps the cold at bay. This b'Twin inflator is compatible with most threaded cartridges from other brands."

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

Fits any threaded CO2 cartridge- 12, 16 or 20g.


Compatible with Schrader and Presta valves.


Max. pressure:

700x23C: 9 bar / 130 PSI

26" x 1.95": 2.7 bars / 39 PSI


Quick, effortless inflation in a matter of seconds.


Ultra compact, can be kept in a saddle bag

Rate the product for quality of construction:

It's cast alloy, not CNC-machined. Plus the logo is screen-printed on rather than laser-etched and was already wearing off on opening. That said, the head has a heft to it that implies solidity, and the blue alloy valve receptacle is sturdy enough.

Rate the product for performance:

The controllability of airflow, ergonomics and end result far belies the £8 price.

Rate the product for durability:

Aside from the screen-printed logo, it looks pretty durable.

Rate the product for weight (if applicable)

At 32g it's hardly heavy, though Genuine Innovations' Elite is only 17g…

Rate the product for comfort (if applicable)

The angle of the head is spot-on for accessing valves and controlling flow.

Rate the product for value:

At £8 including a cartridge it's stunning value.

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

Very well indeed.

Tell us what you particularly liked about the product

The controllability once underway – I felt like I was able to fine-tune pressure without risking overfilling.

Tell us what you particularly disliked about the product

The look could be more pro – but then it's eight quid and will live inside a tool roll. And I wish the head itself was insulated – it deserves a wrap of tape or something.

Did you enjoy using the product? Yes

Would you consider buying the product? Yes

Would you recommend the product to a friend? Yes

Use this box to explain your score

I marked it down on build finish and for not having any insulation at the head which would afford even better control,  and it could be lighter. Otherwise it's excellent.

Overall rating: 8/10

About the tester

Age: 43  Height: 183cm  Weight: 72kg

I usually ride: Merida Ride 5000 Disc  My best bike is:

I've been riding for: Over 20 years  I ride: A few times a week  I would class myself as: Expert

I regularly do the following types of riding: club rides, general fitness riding, fixed/singlespeed, mountain biking and Dutch bike pootling

Living in the Highlands, Mike is constantly finding innovative and usually cold/wet ways to accelerate the degradation of cycling kit. At his happiest in a warm workshop holding an anodised tool of high repute, Mike's been taking bikes apart and (mostly) putting them back together for forty years. With a day job in global IT (he's not completely sure what that means either) and having run a boutique cycle service business on the side for a decade, bikes are his escape into the practical and life-changing for his customers.

Add new comment


bobinski | 8 years ago


Does the canoniser have to be discharged all at once? Your posts suggest not.

Grizzerly | 8 years ago
1 like

So good I recommended it twice!  1 

Grizzerly | 8 years ago

I bought one of these in Wilko.  I've only used it once, but it did the job perfectly.   Unbeatable at the price. 

Grizzerly | 8 years ago

I bought one of these in Wilko.  I've only used it once, but it did the job perfectly.   Unbeatable at the price. 

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