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Kalf Flux Transition Wind Proof Jersey



Smashing weatherproof jersey for unpredictable warmer days at a great price – highly recommended

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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Wow, Kalf has really impressed us with its new range of products this summer. We loved its bibs, Chevron summer jersey and mitts, scoring all of them highly, and I have to tell you that this, the Flux Transition Wind Proof Jersey, might be the pick of the range. It's available nationwide via Evans, and it pretty much nails the newest niche on the block: the lighter-weight windproof jersey.

The Transition is made from two very different fabrics. At the front is a three-layer fabric laminated with a high performance windproof membrane, and the rest of the jersey is made from a lightweight fabric woven from ASKIN yarn, claimed to be soft to the touch, cooling, breathable, fast drying and with UV protection.

> Find your nearest Evans store here

The windproofing covers the front of the torso and also the front and outside of the sleeves, and is very effective. Kalf told us that it's also treated with a durable water resistant (DWR) coating and the membrane is rated to give water resistance to 10,000mm and a breathability rating of 10,000g/m2/24h.

Kalf Flux Transition Men's Wind Proof Jersey - sleeve.jpg

I've used it in a range of conditions and it excels on changeable days when the temperature is the teens. Unless I'm pootling, I get too hot in a Gabba once it's much more than 10 degrees, and so this fills a useful gap in the wardrobe for me. It's not a jersey for hot summer days, at least not for me, as the windproofing would mean I get too warm; I'd typically eschew water protection and just get wet if it rains on hot days.

The use of a very stretchy and breathable fabric for the sides and back of the jersey offers a number of benefits. Firstly, it helps with the fit. As with the Chevron jersey, the fit here is pretty much spot on if you like your jersey to sit close to you. It's certainly not tight like some jerseys where you have to yank the two halves of the zip together to get it on, and it's certainly not flappy or baggy; it's like the third bowl of porridge – just right.

Kalf Flux Transition Men's Wind Proof Jersey - hem.jpg

My 39in chest makes me a medium per the sizing guide, and the supplied medium fits beautifully. That's not me in the pictures, but our model Ash is the same height and weight as me. The close fit is facilitated because of the give in the back and sides of the fabric, as the softshell fabric at the front is not stretchy.

Kalf Flux Transition Men's Wind Proof Jersey - chest.jpg

The second benefit of the combination of fabrics is to help prevent overheating. Humidity in the armpits can quickly escape and heat is easily shed from your back too. If you're going hard on a warmer day, you may find you want to open the zip a bit, as with any windproof, but in general I found that it works really well in the range of around 10-18 degrees. Skin comfort across the front of the chest is improved on warmer days through the use of a mesh baselayer underneath, although I was fine without this throughout most of the testing.

Kalf Flux Transition Men's Wind Proof Jersey - back.jpg

Kalf hasn't overlooked the details, and there are some unusual touches here, most notably with the pockets. At the back you have the regulation three pockets with a zipped pocket on top of the central one that's large enough to keep a large modern smartphone safe (but not dry). So far, so standard. But then – what's this? Carry on round to the sides and Kalf has stuck a further pocket either side of the normal three, sitting around your hips.

Sounds odd, and the first few times I wore the jersey I simply forgot they were there. They're made of the same stretchy material as the back panel and so if you don't put anything in them, they sit flush and don't catch the wind at all. They're great for putting things like gels in, making it just a bit less of a contortion to access the contents while riding. I put my keys in there to see if they fell out (we take the risks so that you don't have to, reader) but the material clung tightly to the bunch and there was no way they were going to get ejected.

Kalf Flux Transition Men's Wind Proof Jersey - riding.jpg

What's that you're saying? How does this compare to the plethora of other windproof, water resistant jerseys now available? Well I'm glad you asked. It is notably lighter-weight and less insulating than the Castelli Gabba, Parentini Mossa and the Orkaan from Stolen Goat, and has much more in common with the Perfetto that Castelli added to its range last year. That has a similar arrangement of lightweight windproof fabric on the front and a more breathable and elastic fabric on the back, with the main difference being the Nano Light Pro fabric used on the back of the Castelli top has a water-resistant coating. The Perfetto is significantly more expensive at £125 RRP, although is widely available online for a lot less than that.

> Design classic: Castelli's Gabba

The Transition is only available in the dark colours seen here, dubbed Merlot by Kalf, and to my eyes it looks pretty smart. There is subtle branding on the front – just a couple of Ks – and then a rather pleasingly psychedelic reflective decal on the back. Rapha-esque styling meets Castelli performance at sub-dhb prices, anyone?

Kalf Flux Transition Men's Wind Proof Jersey - pocket.jpg

As you'll have gathered, I was really impressed with the Kalf Flux Transition jersey. Sure, you could argue that a gilet over a regular summer jersey could give you similar protection from wind and rain, although I really liked how that protection extended to the front of the upper arms here. My first thought about the pockets was "is it just a gimmick?" but having used it, I found myself wishing that some of my other jerseys had the same feature for those really long rides where you need to carry lots of stuff.

Throw in careful detailing and the surprisingly keen pricing – £20 less than the dhb Aeron Rain Defence jersey – and I reckon Kalf and Evans are onto a winner here.


Smashing weatherproof jersey for unpredictable warmer days at a great price – highly recommended

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Make and model: Kalf Flux Transition Men's Wind Proof Jersey

Size tested: Medium

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?

Evans says: "The Kalf Transition Jersey is a high-performance jersey designed for variable conditions. A lightweight, water-resistant and breathable softshell front panel keeps the wind and cold at bay; the lightweight fabric back panel uses ASKIN yarn that is soft to the touch, cooling, breathable, fast drying and offers UV protection. Five open pockets mean storage for long training rides, along with a zipped pocket for valuables."

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

5 Rear Pockets

In addition to the usual 3 rear pockets the Kalf designers added 2 side pockets for quick to reach items such as gels or keys

Windproof Membrane

The windproof membrane is an ultra-thin windproof layer laminated which delivers complete windproof protection, cutting out the wind chill that lowers your core temperature.

Rate the product for quality of construction:

Impressive quality of fit and material.

Rate the product for performance:

Super windproofing from well-positioned panels on the torso and arms. Breathable panels out of the wind help ensure comfort. Novel six pocket arrangement works very well.

Rate the product for durability:

No issues in testing.

Rate the product for fit:

Close, racy fit.

Rate the product for sizing:

Sized as per the chart on Evans' website.

Rate the product for weight:

Pretty light actually – usefully less than the similar Castelli Perfetto.

Rate the product for comfort:

If you're going hard, a mesh baselayer is a useful addition (like with most windproof jerseys) but in general this is a really comfy top.

Rate the product for value:

Cracking value this. I'd argue it has Rapha-esque style and Castelli-esque tech performance, for a lot less money than either.

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

Went through cool washes without a problem.

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

Very well indeed – I am impressed.

Tell us what you particularly liked about the product

Style, perfect windproofing for days when it's a bit warmer than typical Gabba weather. Some protection from rain. Excellent racy fit.

Tell us what you particularly disliked about the product

Not much.

Did you enjoy using the product? Yes

Would you consider buying the product? Definitely

Would you recommend the product to a friend? Yes

Use this box to explain your score

It's hard to fault, really, and with an established premium brand on it I would think it could be sold for comfortably more. If I could give it 9.5 I would.

Overall rating: 9/10

About the tester

Age: 37  Height: 188cm  Weight: 78kg

I usually ride: On-one Bish Bash Bosh  My best bike is: Rose X-Lite CRS

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

I regularly do the following types of riding: road racing, time trialling, cyclo-cross, commuting, touring, club rides, sportives, general fitness riding, fixed/singlespeed, mountain biking

Jez spends his days making robots that drive cars but is happiest when on two wheels.  His roots are in mountain biking but he spends more time nowadays on the road, occasionally racing but more often just riding. 

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nowasps | 5 years ago

Second bowl of porridge, surely?

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