Tested: Fox Union BOA Flat Shoes

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Fox’s new Union BOA shoes are some of the cleanest looking flat pedal options on the market, with a high end feature set and the price to match. So how do they stack up against other flat pedal classics?

In a Nutshell

• Size Tested: 10 US
• Weight: 428 g
• Features:
• Dual BOA® Li2 system secure, on-the-fly adjustability
• Ultratac™ outsole balances grip and durability
• Custom hex shaped lugs engage with flat pedal
• Reinforced toe for protection against rock strikes

• MSRP: $225

The Fox Union BOA is available now.

Intro

For years it has felt like most mountain bike shoe brands view flat pedal riders as second class citizens, not deserving of all the technology, bells, and whistles that they invested into their clipless shoe options. Brands routinely launch “all new” shoe collections that come with a full complement of cleat-box-equipped shoes at a range of price points and feature sets, and then maybe drop a flat pedal option that’s positioned as a “casual” or skate park shoe.

While I understand that rationale - clipless customers do tend to be more open to spending absurd amounts of money on shoes sporting questionable features and promising marginal gains - it’s also super frustrating. I ride my bike a lot. I care about my equipment, and I care about my footwear, even though, thanks to a knee injury, I’m pretty solidly relegated to flat pedals for all of my riding these days. All of the rationales behind high tech features and closure systems apply to my shoes, even though they don’t have cleats bolted to them. Give us more premium flat pedal options!

Apparently someone at Fox agrees with me. The Union BOA is a high-end, high-priced, high-zoot flat pedal shoe. It features two BOA Li2 dials on each shoe for easy adjustment, along with an adjustable insole system, and a sleek, classy exterior. So, are these my holy grail, the shoes that are finally going to shut me up? Not quite, but they will really appeal to a lot of riders.

Fit

I have weird messed up feet. They are my feet, not yours, and if your feet are anywhere outside the bell curve of “normal” you already know that you ought to try on any footwear before you buy. But here are my impressions. I could probably get away with a size 9.5 Union BOA, but really like the fit of the 10 for my high volume feet. It gives my bony protrusions more room to breathe. I’ve found that ski boots featuring BOA’s H+i1 open up opportunities for folks with atypical feet to size up and then cinch down their boots, and I think BOA shoes deliver some of the same promise. It’s easier for me to size up a BOA-equipped shoe and then adjust the fit than it is to do the same with traditional laces.

That’s especially true with the Li2 dials on the Union BOA, which can be adjusted click by click both in and out. I like to start a ride with my shoes very tight, and then gradually back them out as I warm up and my feet swell.

Overall the Union BOA fits true to size, offers nice heel hold, and has a wider-than-average last. They come with swappable shims for the insole, which I very much appreciate. I swapped in the high arch option for more support, and I wish more shoes offered this feature, instead of requiring aftermarket insoles.

In defense of BOA

BOA gets a bad rap. I understand the reasoning behind that – the system adds cost and complexity to shoes, and everyone has had a BOA failure experience, or seen a buddy’s BOA fail. In my line of work (gear reviewing both winter and summer products for the last decade or so) I’ve probably seen more than my fair share of those failures, but I still yearn for good flat pedal bike shoes with a well-executed BOA system. Why? I remain convinced that it’s “better” than laces in a performance footwear application.

BOA is easier to adjust, it transfers tension more efficiently, it holds up better when things get wet and grimy, and it allows for a more precise fit than I get from laces. BOA executed well is a delight to use. BOA executed poorly breaks quickly and requires immediate and lengthy repairs.

The BOA execution on the Fox Union is almost perfect. Here’s what it has going for it:

It uses two BOA dials (and they’re the nice Li2 two-way dials) on each foot. That means that you can independently adjust the forefoot and instep pressure. If you have normal feet, this probably doesn’t matter. If you’re a weirdo like me, it means you can cinch the forefoot down tight and leave the instep nice and loose.

The cables running out of those dials are A) adequately long so that the shoe can truly open all the way up and B) run through plastic eyelets. Whenever I see a shoe with BOA cables routed through webbing loops I can bet that those loops will fail before anything else on the shoe, and render it useless.

The downside, which I’ll get into later, lies in the placement of those loops. But generally, other brands take notes, this is a great recipe for success.

Grip and performance

No, these soles don’t have as much grip as 5.10s with Stealth rubber. No, they do not stick like Specialized’s excellent 2FO. Instead they feel pretty similar to Shimano’s GF6 . They’re absolutely adequate, but not groundbreaking. Pair them with a pedal that bites back , and I’m happy to ride them anywhere, anytime.

They don’t have the stiffest shank around (again, they feel similar to the GF6) but I never thought they were too soft, which is something that I’m hyper aware of given my weak arches.

The Union has a really sleek styling (I’m a sucker for the full monochromatic look) and there aren’t many nooks and crannies for dirt to stick to or water to invade. When they do get wet they dry quickly, and they’re comfortable and well vented. They’ve also held up really well so far, with barely any noticeable sole wear after 20 or so rides. Combine that performance with the ease of use of the BOA system, and you’ve got a winner. So what’s the catch?

The downside (for me)

I think that this is more a personal foot problem than a Union BOA problem, but it’s worth mentioning, since it’s been a little frustrating. The placement of the lowest cable eyelet on each shoe sits right at the crease where the shoe bends when I’m walking. That means that with every step, that rigid plastic eyelet digs right into one of the most sensitive parts of my foot that’s been tenderized by ski boots for a decade. Sustained walking in these shoes leaves me hurting. And, as my friends know, I like walking my bike.

It’s never been an issue while pedaling, and I think folks with lower insteps and less battered and beleaguered nerves and bones in their feet will be fine, but it’s still worth mentioning. I noticed it immediately, as soon as I put the shoes on, so if you can try a pair on at a shop you’ll know right out the gate whether or not they’ll be comfortable for your feet.

What kind of rider will get along well with the Fox Union BOA Flat?

This is one of the cleanest, coolest flat pedal bike shoes I’ve seen. It’s really easy to get on and off, the BOA dials are excellent, the grip is adequate, and the performance is great. So if you’re comfortable walking in them, or you don’t spend as much time walking in your bike shoes as I do, and you’re looking for a premium flat pedal shoe, the Fox Union BOA Flat is a great option.