Stiff upper and detached cable means tricky on/off
High price for category
Flimsy cable guide
Specialized is very clear in its positioning for the Audax – it’s specifically designed for the endurance or gravel-road crowd and not necessarily for racers or casual enthusiasts. However it works if you’re primarily an endurance rider who only occasionally races. The upper is quite stiff, so getting your foot in or out can be a hassle (triathletes beware), and the boa cable can be unwieldy too. Ventilation/drainage is minimal.
Stiffness/Power Transfer The Audax is surprisingly stiff and responsive for a shoe designed for endurance riding, although not to a fault, but not quite as light as we’d expect from Specialized. In endurance shoes extreme stiffness can cause discomfort over the long haul of a century ride, for instance. There was minimal flex underfoot for efficient power, and just enough in the toes for comfort – although those whose cleats are farther out toward the toes might feel more give under load. Combined with the flatter outsole profile, sustained climbing was efficient and comfortable. And there’s plenty of power on hard accelerations too. Bottom line, the shoe is stiff enough that very few will notice a loss of efficiency, while providing an outstanding platform for endurance.
Fit/Comfort While some riders shopping for an endurance shoe may prefer a more plush interior, we still found this shoe quite comfortable on all day rides. The inner is a bit stiffer than we’d like, but it feels fine once on the foot, and we had no hotspots or rubbing. There’s sufficient dense-foam padding around the heel for a secure cup that holds very well on intense efforts, and I could crank the buckles without any pinching. However the toe box was a bit narrow and didn’t stretch much over the test weeks. And they do not offer adequate ventilation/drainage especially for long hot rides, or if your feet get wet.
Closure System Nothing beats a two-way dial system for quick and ergonomic incremental adjustment, especially on the fly. And Boa’s system is as good as they get, with silky smooth dial and cable action, and reliable holding power. And they’ve proven quite durable over the years, and are easily wrenched or replaced if something goes wrong. And whereas the older models were reversed on the left hand, these tighten in a forward motion on both sides for more intuitive adjustment. That said, this system seems almost like it’s there just so they can say it has a dial. The dial only closes one strap across the instep, with Velcro straps across mid and forefoot – plus the cable is detached so you have to “thread” it each time. Velcro would have been easier and lighter! But it does offer excellent on-the-fly micro adjustment. Routing the cable over the midfoot would have been a more sensible use of a dial closure. But while overall the slightly off-centered wrap is snug and secure, and can be fully cranked without discomfort, the synthetic leather upper is quite stiff making them challenging to put on or take off.
Construction/Durability We’ve already mentioned the durability of the Boa dials and cables, plus they’re easily replaceable if anything should go wrong. And this shoe has the most durable upper material in the group, with a matt finish that seems resistant to scuffs and scratches. After multiple rides there’s barely a visible mark on the uppers – this is especially beneficial for gravel riders. The outsole is quite thin and low-profile, but so far we’ve only been able to cause typical scratches and chips, and it’s doubtful any more serious damage would be inflicted under normal use. One potential weak spot is the plastic tab around which the cable loops and tightens – it seems very flimsy for a critical, high-pressure piece, and it’s not replaceable. But after about a month ours is still in good shape.
Breathability/Drainage The stiff upper material can be a bit warm, even with the large mesh patches over the toes. The mesh cutout underfoot is too small to make a significant improvement. Plus the tongue, though perforated, again allows little ventilation. For a shoe designed for long rides, this can be a major issue on warmer days.