Article by Michael Ellenberger
ON Cloudboom ($200)
Michael is a patent attorney and 2019 graduate of Northwestern University Law School in Chicago. Prior to law school, he competed collegiately at Washington University in St. Louis (10,000m PR of 30:21). He recently finished 2nd at the Chicago Half-Marathon in a PR of 67:43, and was the top Illinois finisher in the 2017 Boston Marathon (2:33:03, 82nd overall). He recently secured a 2:31 marathon PR at the Austin Marathon.
It’s been fun to see how brands handle the carbon-fiber plate “arms race” - no two shoes are really identical, and some (compare On’s Cloudboom to Skechers Performance’s Speed Elite Hyper to Nike’s AlphaFly Next%) are considerably different in composition. At the end of the day, though, all of them exist to serve the same purpose: to get you to the finish line faster.
On’s new carbon-plated racing flat, the Cloudboom, is built for the marathon. Taking On’s existing Helion cushioning midsole and sandwiching a carbon-fiber plate (On’s “carbon-fiber infused Speedboard”), the Cloudboom is here to compete with the likes of Nike’s Vaporfly, Saucony’s Endorphin Pro, ASICS’s MetaRacer, and more. Does it stack up?
Weight: 7.9 oz. / 224g as measured (M8.5), so approximately 8.1 oz / 230g for a US9
Heel-to-Toe Offset: 9mm
Snappy and firm, with a distinct forefoot roll
Handsome, fast look
Helion midsole remains a strong midsole option
Lockdown, though not quite as difficult as the photos would have you believe, is tricky
Overly stiff through the midfoot until toe-off (more rock than roll!)
A more traditional midsole (made of Helion) might give it a little more pop
First Impressions and Fit
Slipping on the Cloudboom is unlike most racing flats; the ankle opening is wider and deeper (coming closer to the laces) than most racers. One keen observer called it reminiscent of a loafer or boat shoe. Indeed, the On does have a wide opening, which makes lacing easy and adds a distinct air of lightweight airiness to the (relatively) heavy Cloudboom.
Once on foot, well, despite On’s distinct midsole design (the Swiss brand’s cushioning was said to be mimicked after a half-garden hose), the Cloudboom feels entirely normal. You wouldn’t suspect the midsole is directly bisected by On’s Speedboard, nor that the Helion pods are porous. Instead, you’ll just feel a stiffy, snappy platform ready to be run in.
The upper is the first area I want to draw distinct attention to - while I think On has done a lot of things right here, there are some tweaks that would make this top-of-class. Let’s start with the good (who doesn’t like good news first?): the super-light construction of the Cloudboom’s mesh upper is immensely breathable and enjoyable; it might be the best material for summer running on any top-shelf racing flat. Fortunately, On has also seen to quality construction sufficient to justify the price by surrounding the laces (and thus the core of the midfoot) with a black, thicker material that reinforces the areas that may receive undue strain. I have no doubts regarding the ripping or tearing of the upper - despite it’s ultrathin profile. Plus, it makes for a really cool looking shoe - unfortunately my pair came slightly stained out of the box, which isn’t ultimately a big deal - but was a little disappointing on a shoe that just looks so slick.
But we also need to talk about that lacing scheme. As previously mentioned, On has allowed a very… large ankle cutout, one that is vaguely reminiscent of a men’s loafer. What that means is that your ankle genuinely feels exposed and free; nearly all the models on On’s website displaying the Cloudboom are going sockless or with no-shows, and I think On intends this large ankle opening to improve airflow and make the ride feel barefoot. And in fact, it does that - but at a price. The lockdown in this shoe, while perhaps not as bad as it could be, considering the size of the cutout, is lacking. I think that reinforcement of the lace box was a significant improvement to the shoe - without that, the lockdown likely would be that bad - but as it is, you’re just going to have to get used to feeling like your foot is coming out of the shoe a little. The good news here is that, over several different runs in several different socks, my foot never actually did come out of the shoe, nor did I experience much ankle slip. It just feels a little loose, and especially on tight corners, like they’re about to fly off your feet - not necessarily the sensation you want when racing.
Again, I don’t mean to pan the upper, because I think On has come really, really close to knocking this out of the park - there just needs to be a more traditional construction to it to ensure a runner’s foot stays in place. I’ll sacrifice the wind flowing across my, uh, ankle for a secure lockdown.
As previously noted, On has sandwiched a carbon-fiber plate (in the form of their Speedboard - a technology we’ve seen, without the carbon, in previous offerings before) between two layers of Helion midsole. I actually really like On’s Helion foam - it’s surprisingly bouncy and responsive, and (as you’ll see in the Ride section, below), I wish it had more of a role here. As it is, though, it’s a pretty firm and springy option - not as bouncy as HyperBurst, but also firmer. I would equate it most to Nike’s React cushioning, and it fits in well here.
And then there’s that Speedboard. A word of caution: you’re going to notice it. On has layered it in-between two rows of their Helion technology, and it has to be more rigid than most plates - whether that’s because it’s literally exposed (see the photos) and thus has to take on some of the absorption role usually handled by midsole foam, or if it’s by choice, I don’t know, but I don’t think this plate has a lot of bend. That’s not necessarily a bad thing, to be sure - especially when trying to work down into faster paces, having a stiffer shoe is a benefit (see: basically any sprint spike) but it does come at the cost of general underfoot comfort.
Setting aside the irregularities of not having a complete outsole (and yes, this tuning will collect rocks), I think On has constructed a durable, grippy, and adequate outsole. The lack of rubberization on each individual outsole pod isn’t an issue.
I’ll give you a Tweet version of this section up front: “It’s stiff.” Seriously, the Speedboard that On has wedged in here is going to get you onto your toes, but it doesn’t do so in the gentlest way possible. Instead, you’re, well, springboarded (pardon the pun) onto your toes. It’s a rocker, rather than a roller, and while it is effective to accentuate turnover, it’s not the most comfortable or forgiving ride. In the plate/foam dichotomy, and in comparison to Nike’s dominant trampoline foam or Saucony’s hybrid cushy foam/plate approach, it seems On has favored the plate. You’ll feel fast, to be sure, but I’m not convinced the energy return is necessarily there. I would have liked to feel a little more of that Helion and a little less of that quick-to-toe-off plate.
We have to give kudos to On for joining “The Great Plate Race,” and I don’t think athletes - including those on On’s high-performance ZAP Fitness team - will be severely disadvantaged by racing in the Cloudboom. It’s a more than competent option, and probably hits its sweet spot in that 10K-Half Marathon range (though I don’t think efficient runners will have a problem taking this to 26.2).
That said - I do think there are some aspects of the CloudBoom that could be improved to make this a vastly more competitive offering. One is, I think, an easy move for On: a more complete upper. Actually, On has produced some of my favorite uppers on trainers in the past (I’m thinking specifically of the Cloudswift!), so this move to pull the upper material away from your ankle and create more of an exposed area just doesn’t quite work for me. A more secure fit would go a long way, and I’m sure the On engineering team is already working on a revised version.
But the other big improvement is a tougher sell, based on what we’ve seen from On so far: a broadening of their Helion midsole into a full-length (non-punctuated) piece, at least on the top (green) layer, to help shield some of that carbon harshness. On is practically defined by its porous midsoles, and I can appreciate that intent to maintain branding - but for optimum racing performance, I wish they had rounded out this midsole with that (quite terrific!) Helion material to help smooth out the ride.
Michael’s Score: 8.3/10.
Adidas Adizero Pro (RTR Review)
The new Adizero Pro has a similar profile to the Cloudboom - it feels a little flatter (i.e. less stack) than On’s offering, but compared to the super shoe monsters like the AlphaFly or even Endorphin pro, both the Adidas and the On look and feel more like pre-2018 racing flats. I think Adidas has implemented this better, though - it’s carbon fiber plate, rather than being the dominant factor in the midsole, is really quite unnoticed until the toe-off. For me, it’s a near-perfect hybrid between old (Adios-era) flats and carbon fiber plating - of course, Adidas has had considerably longer to perfect the wheel. But between the two, I’d take the Adi.
ASICS MetaRacer (RTR Review)
Most of the descriptors above for the Adizero Pro also apply to the MetaRacer; these shoes are the similar of any two 2020-era racers, in my opinion. And so, my conclusion stands: take the ASICS over the On, unless you’re dying for a stiff plated racer.
Brooks Hyperion Elite (RTR Review)
So, now we need to dive into our running-shoe dictionaries. The Hyperion Elite, compared to the Cloudboom’s “stiff,” is quite “firm.” I use this term, “firm,” to largely describe the midsole, in this instance, rather than the plate - Brooks’s DNA Zero midsole is quite hard to the touch and does not rebound even as well as, say, On’s Helion. But what separates the Brooks is that the plate is embedded more evenly; rather than being jammed onto your forefoot by the Speedboard, there’s a more gentle roll, likely owing to the higher stack. I am imagining that a more rounded-out Cloudboom would actually feel quite a bit like the Hyperion Elite, or even the upcoming Elite 2, owing to the liveliness of Helion - but, without testing it (or it being a real shoe!), I can’t say. Take the Brooks.
Skechers Performance Speed Elite Hyper (RTR Review)
Like the On, I think the Skechers Performance offering is, despite the advertisements, better suited to events less than 26.2 miles. And, like the On, I found the plate in the Skechers slightly jarring and aggressive. Where the Skechers ultimately triumphs over the On is its midsole - while Helion is good, Hyperburst is the best. The Cloudboom and Speed Elite are pretty similar, actually - but the bounciness of the Elite wins out.
Saucony Endorphin Pro (RTR Review)
Saucony’s new Endorphin Pro remains the closest competitor to Nike’s Next% offerings (Vaporfly and AlphaFly included). While Saucony doesn’t quite reach the bouncy-trampoline heights of Nike, the effect is there, and On can’t quite compete. Take the Saucony.
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