Around for a couple of seasons, you wouldn’t confuse the graphics, shape and materials on Fox’s long sleeved Flexair Pro jersey with any kind of hybrid road cycling or hiking jersey. This is a top clearly designed for MTB, and using a complex blend of fabrics across different zones, one of the most technical riding jerseys on the market.
The main body is cut with an articulated, figure-hugging shape that’s slightly more athletic than most boxy riding jerseys, and the Flexair Pro fabric technology line-up includes Polartec Delta, Dyneema and Carvico sleeves - all three of which I needed to dive into google to see exactly what they were offering.
Design and specifications
There’s a flat bonded hem, neck and cuffs for a more low-profile fit that also saves weight, and the rear hem extends lower, so the jersey has good coverage and doesn’t ride up while you reach forwards on the bike.
Fox’s front panel uses Polartec Delta, which is a textured, perforated woven fabric designed to loft the material off skin to improve air flow and wick moisture faster. Delta is also made up of at least 50 percent recycled PET plastics and claims maximum breathability while wet as well as being the ‘world’s most cooling fabric’.
The gist of its performance claims are not drying as quickly as other fabrics and radiating any moisture within the texture of the fabric to cool the body while working hard. Even after watching a video on how it all works though, I’m still not quite sure exactly what it's doing in terms of holding moisture in a lattice ‘matrix’ in the middle of the fabric.
Elsewhere on the Flexair top there is a more perforated, aerated fabric weave on the back to aid ventilation and dump heat and a silkier, smoother fabric called Dyneema on shoulders and sleeves. This is a composite material that’s lighter than nylon and also ‘dramatically increases tear, puncture and abrasion performance’ over commonly used materials. This smoother part of the jersey has lazer-cut vent holes and is more scuff resistant and protective against snagging and ripping.
Fox’s Flexair Pro jersey might be packed with all this fabric technology, but it’s also simply a very lightweight, free flowing jersey that feels thin, comfy and stretchy once on. There’s no sense of the tighter cut being restrictive or clingy on arms or anywhere else (even when wet) and the low-profile hems and cuffs give it a really invisible feel with no riding up or stickiness at the extremities.
Fox’s material lasts really well out on real world trails packed with often sharp vegetation and is very resistant to pulls and snagging, so it doesn’t get all bobbly and tired looking too fast – like some rivals.
Extremely breathable and airy, ventilation and cooling are effective, but it’s not to the point where you feel like you’re totally naked and exposed with a gale blowing in onto the chest – more of a diffused cooling. I’ve rode it with a mesh baselayer underneath and been warm enough on fall/autumn days, so it’s definitely not one of those total ‘mesh tea bag’ tops that lets all the wind and chills in when rolling a bit faster.
The more open mesh on the back really dumps heat build-up and lazer cut perforations in the arm pit areas seem effective at regulating heat in that zone too, and, considering the smoother sleeve fabric looks like it it’s going to be warmer than it actually is, the Dyneema panels perform great by being a bit tougher without any stuffier as well.
On hotter days, you get more of a sense of Polartec’s claims about how Delta works, as the fabric does seem to sort of stay ‘damp’ when working really hard, rather than getting totally saturated, soggy and clingy. The brand claims this keeps you cool, but it’s hard to quantify this compared to other tops, other than saying I never felt too stuffy or boiled, and back up Fox’s claims that the material resists getting overly sodden and heavy.
The Flexair Pro is also a pretty fast drying to recover fast if you do fully soak it with sweat (although arguably not quite as fast as Rapha’s Technical Tees). Wearing it in the French Alps in really hot summer weather, the jersey basically dries fully by the time you’ve done a long descent if you do soak it on the climbs.
Fox’s Flexair Pro is pretty much state of the art for a mountain bike jersey, which is reflected in the high asking price. Fit and styling are excellent, the materials used are tougher than most against snagging and damage and the garment’s breathability is excellent. With some killer deals around online, it’s a great option, but at full RRP, other similar performers like Rapha’s Technical Tees are slightly cheaper.