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Fox Union Boa: Real World Review

7.8K views 10 replies 7 participants last post by  Jayem  
#1 ·
Hey all,

Since I haven't seen anything pop up on this forum about these shoes, I figured I'd share my initial impressions.

For a little context, I've been riding clipless pedals since ~1996 and have ridden a ton of different shoes during that span. From Answer, to Diadora, to a couple Shimano offerings, to Specialized, to Sidi (3 different models), to Pearl Izumi, to a couple versions of the Ride Concepts to the Fox Union Boa. I mention this because like any person, I can only base my perceptions of value on my personal experience, and because naturally, I consciously and subconsciously compare each new thing to those that came before.

So far the Unions have impressed me. Straight out of the box, I was fairly impressed with the style. Mine are the black colorway and I appreciate the subtle low-profile look. Coming from the last 2 generations of the RC Transitions, the toned down, less boxy look is something I appreciate. So far, I am feeling the build quality with their molded toe and welded seams, but we will see. I felt the same way about the latest RC shoe until they began to separate. They also clean up really well. I splattered them up pretty well in a bit of a mud fest this weekend and they cleaned right up with a damp rag.

As far as fit, there are a lot of things to like. They can't compare to the Diadora of the mid-ninties for comfort, but what can? Those were simply the most comfortable pair of shoes I have ever worn on or off the bike. I wear a 44.5 and the Unions fit spot on. While snug, they do not encase my foot like a Sidi. I love the elf shoe fit on the gravel and spin bikes but not on the Trail bike. The toe box is roomy without being boxy. I'd pit them somewhere between the RC Transitions, which are incredibly tight for being so boxy, and the version of the Pearl Izumi X alp I rode 5-6 years ago, which were roomy to the point of absurdity. And, for those that need a little extra arch support, the Unions come with 2 different easy to use inserts. I experimented with the high arch support, but it was a bit much for me. These could, however, be a game changer for someone with high arches.

I think the thing I appreciate the most about the Unions is their heel cup. For whatever reason, I have a heel that loves to lift out of bike shoes and have struggled for years to match the heel cupping prowess of the Sidi Dominators. I think I still give the edge to the Dominators, but by only a small margin. I ended up on an ill fated "ride" a week ago that basically turned into mountain climbing while toting along my bike and the Unions handled it really well. Their tread compound while not as grippy as the Sidi Gravel or Shimano XC3 definitely allowed me to climb something like 600 vertical feet in a quarter mile. It was basically a goat trail and I did not slip around much or experience any heal lift.

Now on my fourth shoe with a Boa system, I am cautiously optimistic. Without a doubt, I prefer the Boa to laces, but still have not found anything I liked as mush as the Sidi ratchet of old. The Boa system is great for a dialed nuanced fit, and the dual Boas on the Union really help secure my oddly shaped boney foot- I do have one strange rub where the tongue meets the top of my left foot, but that seems to be going away as the shoes break in. But, when Boas get dusty and dirty, they tend to bind. I once got trapped in my Sidi Gravel after an arduous day bush-whacking by gravel bike in the back country. For one last note on the Boas, I am having a hard time getting used to the two dials jutting off the side of the shoe. I have read about them getting caught on brush, and while I cannot attest to a similar experience, their odd placement makes this seem likely.

Set up was really easy. I do think the whole power/control arrow is kinda silly, but the cleat mounting surface has plenty of fore aft spacing options. The cleat may not sit quite as far back as on the RCs but there is a lot of room to get the cleat pretty far back for those that want that. I prefer to set the cleat just behind the ball of my foot and a uniform set up was simplified by the elegant inclusion of spacer lines. I'm not sure why more shoe companies don't do this, but it's a great detail.

As for ride quality, the Union has a fairly stiff sole for constant and reliable power transfer. I haven't been out for more than 15 miles 2 hours, but so far these shoes have not given me the impression that they will develop hotspots. I will have to wait and see what happens when the weather changes and longer rides are on the table. Basically, these shoes disappear while riding, which is one of the best compliments I can give a bike shoe. While riding I don't think about them at all. It has been cold and wet around here (Bay Area, California) but these shoes shed water from a couple low level stream crossings and puddle splashing pretty well. Plus, they kept my feet reasonably warm; not RC warm, but those were extra toasty-great for the winter, less so for the summer.

At $250 a lot of people will balk, but I've been spending $150 - $350 on MTB shoes for 25 years, so the price point feels right in line with the build quality. Overall, I think these are a solid, well-designed shoe and while they are not the absolute best at any one thing, they receive high marks from me in every category, making them a down for whatever MTB shoe.
 
#2 · (Edited)
Great review- thanks much! I’m intrigued by the Unions. Can you weigh them and let us know? My go-to shoe for the last few years is the FiveTen Hellcat Pro for their fit, protection, relatively low weight and decent power transfer. The Unions look very similar and the convenience of the boa could give them the edge for me. 👍👍
 
#3 ·
Sorry for the delay, I've been away for work. The Unions weigh 2 pounds 4 ounces as a pair with cleats installed. Used my postal scale to weigh them.

These are lighter than my RC Transitions @ 2 pounds 6oz, but not as light as my Sidi Gravel at 2 pounds even w/cleats.
 
#5 ·
Wow, has it been that long already? They have held up really well. I have no complaints what-so-ever. When I actually clean them they still look new. I haven't had any binding, no hot foot, none of the materials/ seams have signs of wear. They have just been super comfortable and reliable. It'll probably be a few years, but when/if these wear out, I'll get another pair.
 
#6 ·
For anyone with the clueless version, any thoughts on foot pain? Shoes are great, feel awesome but on rough trails the outside of both my feet are so sore. I literally had to take a break on a DH. I have the cleats 90% back but not completely,

Struggling a bit and went back to specialized recon 3.0. These shoes I have no pain, ever, amazing in all ways except they have zero protection.

Any thoughts? Is it the flex of the shoe? They feel stiff but obviously not as stiff as the carbon recon 3.0. There is not excessive movement or anything. They are the correct size... The outer side of both feet 3" from the pinky toe back.

Much appreciate any advice,
 
#7 ·
Insole? I've found that sometime I need an insole, like superfeet black for comfort.

Sometimes shoes aren't comfortable... I remember first switching to clipless shoes with a set of Shimano ME7s and I didn't like them... too stiff and experienced foot pain. Switched to Specialized 2FO Cliplites, which offered a bit more flex and I loved them.

Recently came back to trying the ME7s and love them... go figure. I had just bought a set of Specialized DH clipless wanting more toe protection than the 2FO cliplites, but one ride and I didn't gel well. Way too much room in the toe box.
 
#9 ·
Funny to see this review talking about heel retention. I just ordered and returned a pair of Unions. They were too narrow and uncomfortable for my feet, but one thing that really stood out was how easily my heel lifted. Way worse than the other shoes I tried on at various shops over the last month (Shimano, endura, five ten and bontrager rally). I bought the bontragers partly because they had the best heel retention, by far.