Adidas adizero jersey

Hill-climb season is fast approaching and the adherents of this particularly savage form of two-wheeled suffering divide their time between gasping practice runs on the local gradients and wondering how many of the bolts holding their bike together they could do without. Weight-saving is taken to extremes with saddles weighed, front mechs and unnecessary chainrings dispensed with, caps removed from headsets and helmets from heads. Pity the hill-climber, then, who forgets the weight of all those clothes that he's unthinkingly hauling up the hill with him. What he needs is The World's Lightest Jersey. And that - according to Adidas - is what we have here.

The Adizero Jersey floats in at a almost-not-there-at-all claimed 65g (our Large weighs 70g), making it whole tens of grams lighter than the next lightest jersey we could think of. The Castelli Climbers' Jersey weighs 91g, and the Rapha Super Lightweight jersey that we reviewed recently is miles off the pace at a portly 140g, putting it only slightly lighter than a plethora of jerseys which make no particular claims to be Really Really Light™. In their launch marketing, Adidas made prominent use of a helium balloon apparently supporting the Adizero, which might give the aspiring grimpeur pause for thought.Perhaps instead of starving himself and spending a grand on those special climbing wheels, he should merely attach a helium balloon or two before setting off up the hill.

Mindful of covering all of the weight-saving bases, this jersey will also aid your hill-climbs by making your wallet lighter. A lot lighter actually. £120 is quite a price for a jersey, especially one that reminds you of a plastic bag when you first remove it from the packaging. It would be fair to say, then, that I wasn't immediately convinced by the Adizero.

Taking a closer look at the construction of the jersey, the plastic bag jibe was unfair. The front panels are made from a super-lightweight ripstop material a little like that used in parachutes, made of 88% nylon and 12% spandex for a very limited amount of stretch. It's extremely thin but offers some wind-resistance while still keeping some breathability. The side panels are made from a very fine polyester mesh, and a different, softer mesh is used for the main part of the back. The raglan sleeves are made from a fourth type of fabric, a very fine lycra-like material, except for the sections underneath which are the same mesh panel as the sides of the torso. Being so lightweight, it all feels incredibly flimsy and prone to tearing at the slightest provocation. In fact, the various fabrics are surprisingly strong and the stitching has been reinforced at all the points where a seam might start to come apart.

At the ends of the sleeves and around the bottom of the jersey is a 14mm strip of sticky silicone, intended to keep everything in place. On most jerseys with silicone grippers, it is added to an elastic hem such that the stretch keeps the silicone pressed against your skin or bibshorts. Here the hems aren't very elastic at all, meaning that unless your biceps and abdomen are just the right size, the grippers don't actually grip that much.

Big Dave was our model for the photos, and as you can see, the Adizero is quite a tight fit on him, not that surprising as he generally wears an XL in most race-fit jerseys. On my lesser frame, the fit was looser than I'd really want for a race jersey - an M would probably suit me better. Perhaps Adidas is basing its sizing on compatriots such as Marcel Kittel rather than on tiny Italians. The sleeves in particular don't sit smoothly on my arms and I'd say they are too loose for the majority of racing cyclists. Generally the aerodynamics are rather less well-resolved than on Castelli's Aero Race jersey, and sizing is a world apart; I could only just fit in an XL of the Aero Race. In fairness, the focus here is on weight above all else, and in a hill-climb your aerodynamics might not be so crucial.

Making the back of a jersey out of mesh got a bad press at the start of 2014, after Chris Froome got a bad case of sunburn while out riding in Rapha's revealing mesh skinsuit. I spent a long sunny day riding in the Brecons in this jersey having also forgotten the suncream, and to my surprise had no such problems. Wearing suncream is probably a wise move on a hot day when using this jersey, but I'd surmise that it's less translucent than Rapha's mesh.

The Brecons were a good test of the Adizero in fact. Not - I'm afraid - that I could feel an increase in climbing speed resulting from the 100g saving over a "normal" summer jersey. But it's actually a very effective piece of gear for a warm day's ride with fantastic ventilation for the climbs and just the right amount of protection from the wind for the fast descents. "Light makes fast", it says inside the neckline. I couldn't feel (or measure) myself going faster, but light makes comfortable as well: the feeling of a jersey so light it's almost not there is odd but pretty pleasant. The ripstop material used on the front is slightly scrunchy (leading to my earlier comparison to a Tesco bag) and this had made me expect a damp and sweaty experience, but this wasn't the case.

At the back there are two rather than the conventional three pockets, with the mesh continuing downwards in the middle where the third pocket would generally be. The pockets aren't exactly huge either, but let's be honest, if you've bought a 70g jersey you're unlikely to want to cram that much in there. There's space for a phone and a few gels, anyway. I found that if I didn't load the two pockets approximately equally, the heavier pocket would tend to make its way around towards the front, twisting the jersey around my torso. Given that my phone weighs twice what the jersey does, this isn't that surprising. A tighter fitting waist (such that the gripper strip worked) would help to prevent this - again, size down one or two sizes from your usual Italian size.

Wrapping up the details, at the front is a full-length cam-lock zip from YKK - the lightest they make, unsurprisingly - with a garage flap at the top to stop neck irritation. And that's about your lot. It's a pretty full-featured jersey for something so single-mindedly focussed on weight. Comfortable and generally a very pleasant garment on a warm day, the Adizero is well-constructed and with an intelligent mix of different fabrics and meshes in the places you want them.

I expected that the relentless pursuit of weight-reduction would result in compromises. In reality there are a few - the fit isn't as good as you'd expect at this price, the styling is fairly uninspired and the pockets are a bit small. And, of course, it's monstrously expensive. All that being said, this ethereal jersey is a really nice piece of kit for a sunny day in the hills.

Verdict

Very expensive, insanely light and surprisingly comfortable; fit could be improved