Like this site? Help us to make it better.


B’twin 900 Ultralight Showerproof Cycling Jacket



Great lightweight jacket for changeable conditions

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.

What the scores mean

Good scores are more common than bad, because fortunately good products are more common than bad.

  • Exceptional
  • Excellent
  • Very Good
  • Good
  • Quite good
  • Average
  • Not so good
  • Poor
  • Bad
  • Appalling

The B'twin 900 Ultralight Showerproof Cycling Jacket is a lightweight, compact model designed to keep you dry and comfortable in showery weather. I've remained temperate and generally arid for several hours a time on some very showery September saunters and faster-paced blasts.

It's made of a very thin, translucent, 100 per cent polyamide material designed to reveal club colours. The specification is very high, broadly on par with a couple I've used long term and costing almost three times as much. The fabric is claimed waterproof to 3000mm, or roughly three hours' worth of persistent precipitation.

> Find your nearest Decathlon store here

As you might expect, it's windproof too. Taped seams reinforce this assertion and ventilated panels (located discreetly around the armpits and shoulders) theoretically encourage moisture eviction, while keeping wet stuff from being funnelled inside on wet, blustery outings.

Btwin 900 Ultralight Showerproof Cycling Jacket Grey - shoulders.jpg

Does it all work? It certainly does. Overall performance has been excellent. A muggy though wet September, with temperatures typically climbing into the high teens, has confirmed it delivers in pretty much every respect.

To some extent, factors such as base/mid-layer and rider thermostat will play a part, but wicking is pretty seamless and, aside from some trace mistiness, I've never felt boiled in the bag, even after 40 minutes at full-pelt.

Btwin 900 Ultralight Showerproof Cycling Jacket Grey - riding.jpg

Despite being very thin, it does an excellent job of blocking wind blast. When the mercury slid to single figures, on midnight meanders at a decent tempo, I never felt chill. (And though thin, and a road garment through and through, some singletrack shenanigans on the crosser have failed to tax it.)

It's important to remember that jackets of this sort are designed to resist persistent showery rain, in this instance for around three hours. Provided a garment wicks rapidly, my preference is towards highly water resistant rather than truly impermeable. I've cruised along through intermittent heavy showers for two hours or so quite comfortably in the 900 Ultralight. Heavier rain will make it through the surface but a gentle breeze soon banishes any dampness. (Likewise, following a machine wash it's line dry in around 15-20 minutes.)

> Buyer's Guide: 20 of the best waterproof cycling jackets

Some users have suggested water can sneak in around the collar, which is sensibly proportioned but not fleece lined, so in some situations could permit water to creep inside. I've not experienced any bagginess (it's not me in the photos), which could result in problematic, incremental creep, even when hunkered low on the drops for longer periods, but then again my hair extends beyond the collar, which undoubtedly helps.

Btwin 900 Ultralight Showerproof Cycling Jacket Grey - chest.jpg

I found the overall cut and length of the jacket bang on: loose enough around the shoulders and for a couple of layers underneath, but close enough to minimise flutter. The tail was also just right, offering proper coverage for my lower back without gathering. Elasticated hem and cuffs are similarly reassuring.

he jacket folds into its own pocket, for stowing in your jersey when not required. This pocket makes a decent stash point for energy bars, small bunches of keys and smaller gizmos (it swallowed my super-zoom compact camera and waterproof case without any signs of indigestion, let alone ejection).

Btwin 900 Ultralight Showerproof Cycling Jacket Grey - packed.jpg

As expected, retro-reflective branding is sensibly distributed and just the right side of extrovert.

Btwin 900 Ultralight Showerproof Cycling Jacket Grey - back.jpg

Zippers can be a weak spot at this price point, but here I've had no problems. The tag is of a decent size, too, easily commanded at speed should you want to regulate air-flow. As with most, it's a little remote in full-finger gloves, but looping a cable-tie through it solved the problem.


The 900 Ultralight does exactly what it promises, and continues the superstore brand's reputation for high-performing, wallet-friendly equipment. I've found it vastly superior to the Boardman men's packable jacket which commands similar cash, although my main problem was with the Boardman's cut/fit.


Great lightweight jacket for changeable conditions

If you're thinking of buying this product using a cashback deal why not use the Top Cashback page and get some top cashback while helping to support your favourite independent cycling website test report

Make and model: B'twin 900 Ultralight Showerproof Cycling Jacket

Size tested: Large

Tell us what the jacket 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?

B'twin says: "Designed for frequent cycling in showery weather thanks to it's stretch fabric with a 3000mm hydrostatic head rating.

"Both very light and compact it's a great product for roadies as it folds down easily into its pocket and fits in the back pocket of a jersey and due to it's semi transparent fabric your club colours will be visible.

"It has taped seams & is windproof and, thanks to the stretch fabric, it is quite fitted and worn close to the body. Extra ventilation reduces the build up of condensation."

I'd say it's a lightweight shell that offers decent protection from wind and heavy showers. It performs better than many, especially at this end of the market.

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

100% polyamide, taped seams, single pocket (folds into)retro-reflective graphics, elasticated sleeves.

Rate the jacket for quality of construction:

Well made and backed by a two-year warranty.

Rate the jacket for performance:

Very good overall. Breathes better than others I've used at this price point too.

Rate the jacket for durability:
Rate the jacket for waterproofing, based on the manufacturer's rating:
Rate the jacket for breathability, based on the manufacturer's rating:

Very good by genre standards and the thin material certainly helps.

Rate the jacket for fit:
Rate the jacket for sizing:

Bang on for me.

Rate the jacket for weight:
Rate the jacket for comfort:
Rate the jacket for value:

Very good.

How easy is the jacket to care for? How did it respond to being washed?

Very easy to live with. Pop in the machine at 30 degrees, minimal detergent. Line dry in 20 minutes.

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

It resists moderate to heavy rain remarkably well, while offering decent defence against surprisingly chill autumn blasts. Breathability is reasonably good thanks to rear venting and the thin material, and dropping the zipper provides some instantaneous relief in muggier conditions.

Tell us what you particularly liked about the jacket

Meets the design brief handsomely; well made and competitively priced.

Tell us what you particularly disliked about the jacket

Nothing, given the design brief and ticket price.

Did you enjoy using the jacket? Yes

Would you consider buying the jacket? Yes

Would you recommend the jacket to a friend? Definitely

Use this box to explain your score

It's a very capable garment that can be stowed in a pocket and flung on should the weather turn bandit; highly water resistant yet breathable, and superior to most I've used.

Overall rating: 8/10

About the tester

Age: 43  Height: 1m 81cm  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)

Latest Comments