Fox hit a home run with its latest Union flat pedal shoes, going straight into the shortlist of best mountain bike shoes. Can it do the same with the clip-in versions? I’ve been testing the cheaper Union, and high-end Union Boa (as used by the Santa Cruz Syndicate DH team), to find out.

Design and specifications

Like the brand’s excellent Union Flat shoe, the clip-in model gets a striking one-piece moulded upper that gives an exceptionally clean, modern look. The co-moulded rubber reinforcements stretch around the toe and heel, with perforated pockets to allow ventilation and airflow. And the overall result is an impressively seamless upper that is extremely easy to wipe clean, as there are very few crevices for mud to hide, and the rubber dries quickly.

Securing the shoe, to ensure stability when cranking on the pedals, are traditional laces and a broad velcro strap. Fox has kept the laces short, so they don’t require extra tidying, and the strap could be cinched up pretty tight without creating a hotspot across the top of my foot. It’s doesn’t even out the pressure as well as the dual Boa version, and the lace/Velcro opening was more difficult to get my foot into, but this shoe is significantly cheaper than the Boa option. £60 cheaper to be precise. With that in mind, I believe most riders will be happy to trade a little convenience for a reduced outlay.

The long cleat pockets allows you to run a rearward pedal stance to put more pressure through the pedals and improve DH stability.

Twin elastic gussets keep the tongue in position and Fox has also given the Union Clipless a deep heel pocket, both of which improve foot stability. The heel pocket does have a fairly pronounced, square-edge that I could feel through my sock, and that rubbed slightly when walking and pedalling. In that respect it’s not as cosy as my favourite Crankbrothers Mallet Boa shoe.

One aspect where Fox does have an edge is with its exchangeable arch support. Included with the shoe are two different supports – for high and low – and these can easily be swapped out by removing the insole and using the velcro attachment. It’s a simple but useful way of customising the shoe to suit your foot.

Flip the Union over and there’s an Ultratac rubber outsole and massive moulded cleat pocket with long slots that give an ample range of adjustment (36mm). A thick rubber perimeter moulding and ramps at either end help guide the cleat into the pedal.

Fox offers seven different colours and a size range from 37 to 47 EU.

The wide strap makes tying laces and getting your foot in and out tricky, but keeps the shoe locked down under hard pedal efforts and big pulls.

Performance

Compared to my favourite Crankbrothers Mallet shoes, the Fox Union Clipless has a less bulky upper, with more stability and a slightly stiffer sole. It’s not as cushy and comfortable as the Crankbrothers, which I found most noticeable on long rides and when walking around.

I had no issues getting a good cleat placement, and the sole markings made it easy to replicate left to right. Fox even describes the cleat zones as ‘power’ and ‘control’ to take out the guesswork.

Weight is on par with the Crankbrothers, as is the price considering the Fox doesn’t come with any cleats, and the Crankbrothers does.

The one-piece, rubberised upper it super-easy to wipe clean and dries quickly.

I’ve worn these shoes a lot, and so far they’re holding up reasonably well. There is some minor degradation of the rubber around the lace eyelets and a shallow crease forming on the side of the shoe formed as the sole bends. However, I did managed to rip the laces out of the eyelets, and rip the upper, when I hit a stump with my foot. It was a big impact, but I wonder whether a similar impact on a shoe with more traditional construction would have done as much damage, as there would have been reinforced eyelets and stitching to stop the tear.

A big impact against a stump ripped the laces out of the eyelet. But my foot emerged unscathed. 

I found weather-proofing to be very good considering this is not a specific winter shoe. It stays relatively dry for longer than most shoes, and dries quickly too. Yet I didn’t overheat wearing it in the summer months.