Having received a bit of an update, Fox’s Union Boa Clipless Shoes distance themselves a little more from their more affordable Union Clipless brethren. With the addition of D3O inserts, they bring balanced performance for all weathers, as well as a stiff platform for solid efforts on the pedals. But be sure to size down for the best fit and better comfort.
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Fox Racing Union Boa Clipless Shoes – Technical details
With an all-new look comes a fresh host of features for the Union Boa Clipless. This time, the shoe uses a new upper that combines a TPU-welded construction as well as a ripstop fabric rear. There’s also a D3O pad in the insole to add an extra hint of cushioning. The fit has also changed, which makes the toe box roomier.
Two Li2 Boa dials provide microadjustment across the whole upper of the shoe, and a molded toe cap adds useful protection. On top of that, there are high and low arch support inserts for a hint of fit customisation, and as usual, an Ultratac outsole has been employed to balance durability with grip.
As expected of Fox, there are a bunch of colour options on offer, including black, cocoa brown, dark shadow grey, military green, and vintage white, the colour you see here. There is also a wealth of sizes available from EU37 up to EU47.
But note, Fox says that the fit may be bigger than usual and to consider sizing down, despite also claiming that the fit is uniform across the Union shoe range.
At 504g per EU43.5 shoe, it’s a little weightier than others, such as Crankbrothers’ Mallet Boa Trail at around 455g, and Ride Concepts’ Hellion Elite Boa at a claimed 415g for a EU43.
Fox Racing Union Boa Clipless Shoes – Performance
And with that, the former point rings the truest. I started my test with a size EU44, as usual, and they were certainly too big. Although I still ride in my Union Flat shoes, which are an EU44, and they fit perfectly. My standard size caused discomfort while riding, as the tongue dug into my ankle while I was riding. With that, I went one size down to a EU43.5, and I found the fit to be a lot more similar to the brand’s other shoes, and much better in general.
With a smaller size, I was much happier overall. The shoe is snug where it needs to be, but with plenty of wiggle room in the toe box. I would even consider trying another size smaller.
But with the size qualms out of the way, Fox has delivered a great shoe here. It’s generally rather comfortable. I’m a big fan of the arch support options, too. These add useful fit customisation to the shoe, making for a more comfortable package overall.
Although comfortable on the whole, if I hadn’t paid enough attention when tightening up the dials, I found that the tongue could slip and dig into my ankle again. However, repositioning the tongue and fiddling with the dials fixed this, but it’s not an ideal situation.
Elsewhere, the Union Boa Clipless delivers excellent performance. It’s plenty stiff enough to provide prompt power transfer to the pedals, while providing just enough compliance to stave off foot fatigue. I’m sure that the D3O inserts play a role here too, as they do an amicable job of absorbing harsher impacts and high-frequency chatter.
Thanks to the low profile, not-so-aggressive tread, and shallow cleat box, clipping in and out is a very simple affair, and similarly to Fox’s other clipless shoes, the cleat tracks are fairly long. This means that I’ve been able to place my cleats nice and rearward for a more commanding, comfortable, and stable stance on the bike – an excellent addition for a trail/gravity shoe.
Speaking of the tread, although it is low profile, it provides just enough traction when walking. Granted, over loose stuff, the shoe will slip, but that’s only natural. Everywhere else, there’s been plenty of grip when hike-a-biking.
Where Fox has chosen to go for a mixed upper construction, the shoe brings a good balance between weather protection and breathability. In proper summer heat, the shoe can get a little toasty, and of course, it’s not a shoe built for proper winter riding, but there’s just enough airflow for comfort, and more than enough water protection to keep splashes and water crossings out. Additionally, the TPU/textile mix makes for a great-looking shoe.
Fox Union Boa Clipless Shoe – Verdict
With a price tag of £220, the Union Boa Clipless shoe is certainly a premium trail/gravity offering, and that money puts it right in the firing line of the likes of Crankbrothers’ Mallet Trail Boa, a favourite of mine. While general packaging of the Union Boa, with its second Boa dial and its TPU upper, makes for a more adjustable fit and better weather protection, Crankbrothers’ offering is more comfortable.
It’s a similar story for Ride Concepts’ Hellion Elite Clip Boa at five pence short of £210. This one also gets a pair of Boa Li2 dials and D3O technology. We’ve not tested this shoe just yet, but if the flat pedal, base model of the Hellion is anything to go by, Ride Concepts is onto a winner.
Stylish, functional, and rammed full of useful features, Fox Racing’s Union Boa Clipless Shoe is certainly one to consider. I’ve enjoyed its balance of weather protection and airflow, as well as its stiffness, heft of adjustability, and its looks. However, comfort hasn’t been completely perfect for me, and make sure to double-check your sizing before you take the plunge.
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Product purpose:
Build extra:
Combined TPU/ripstop welded upper
Dual BOA® Li2 system provides on-the-move micro-adjustability and improved power transfer to the pedals
Molded toe cap designed to protect against rock strikes
High and low arch support options for a custom fit
Molded internal stiffening plate optimizes power transfer and off-bike comfort
Ultratac™ rubber compound provides excellent durability and unprecedented grip
2-bolt cleat system compatible with all major pedal suppliers
Product construction
Product construction extra:
Product performance
Product performance extra:
Product weight
Product weight extra:
Product comfort
Product comfort extra:
product value
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