The On Cloudflash is a carbon-plated racing shoe focused on shorter distances. It complements the On Cloudboom, the carbon-plated long distance shoe On launched in summer 2020.
Similar to the Cloudboom, the On Cloudflash is a minimal racer with a lot of ground feel. Let’s find out how it performed out on the roads.
The On Cloudflash comes with great traction. It’s an odd addition to something so race focused. Usually, shoe companies sacrifice traction so a racing shoe weighs less. The Cloudflash outsole really grabs the ground using a multi-level repeating “x” pattern at the heel and forefoot. It’s an ideal pattern for digging into a rubber track during intervals.
Just like with the Cloudboom, the outsole’s got some durability questions. The outsole’s forefoot lugs are showing plenty of wear from my testing. I think you will most likely get 200-250 road miles out of these but I can’t guarantee it. Using a treadmill or track (outside of races) will help avoid extra wear from pavement and extend the shoe’s lifespan.
The upper of the Cloudflash is a single layer of very nice engineered mesh with strategically placed fuse around the lace loops for strength and on the heel for shape. The tongue is made of the same synthetic suede from the Cloudboom and the New Balance FuelCell TC. As with all On shoes, the materials look nice, but there’s nothing here that other racing shoes aren’t already doing.
And while the single layer of engineered mesh makes the shoe feel incredibly light, it’s still heavier than the Nike Vaporfly Next%, the world’s current favorite racing shoe.
The On Cloudflash fits true to size. The achilles pillows and soft foam in the heel really make the heel feel more comfortable than is typical of a racing shoe. You sink in just enough to feel a nice hug. The upper fits much better than the upper on the Cloudboom. The tongue is still slippy, but not as much as the Cloudboom’s tongue. That’s thanks to the more dialed-in fit of the upper.
On’s racing shoes still badly need a gusseted tongue. I’m hopeful those are coming in the next generation. The Cloudflash is much more in line with On’s typical craftsmanship than the Cloudboom.
The Cloudflash has a basic internal heel counter but it’s not very stiff. Additionally, the Cloudflash features synthetic suede internal reinforcement around the edges of the shoe from heel to toe to keep you on top of the footbed. The internal reinforcement also connects up to the front two lace holes to better support the forefoot on tight turns.
The Cloudflash doesn’t need a lot of support because it sits so low to the ground. The drop’s only 5mm so its a relatively flat platform too. The overall support is minimal but strategic, very typical of a racing flat. This shoe can take tight corners and deal with uneven roads as needed.
Just like the Cloudboom, the On Cloudflash features a minimal cushioning setup. It’s way different than any other carbon plate racer and nothing like a modern day high cushion, carbon plate shoe. It’s more like a traditional racing flat. Unless you’re a very efficient runner, I wouldn’t recommend using it for anything above a 5k. Speedy intervals on a rubber track are also a good use case.
Like with the Cloudboom, there’s not enough of the Helion foam to balance out the stiff carbon-infused speedboard. You’ll feel the carbon plate and ground very clearly through the midsole. This is a shoe that’s not focused on cushion at all and it shows.
If you’re an efficient runner with a small build, the On Cloudflash may be a great addition to your running closet as your go-to racing flat. But at a $180 price point, everyone else will find similarly-priced, better cushioned race day options.
Thanks to On for sending a pair to test. On was not given any editorial control of the review. This review is based on our weartesters’ experiences using the shoes for speed workouts, trail runs, treadmill training, long runs, casual wear, and more.