I tested the On Cloudultra 2 on forest paths, gravel, mud, and wet and dry rock. The second generation feels softer, was lighter in my size and proved more comfortable than its predecessor. It is still a substantial shoe for long trail runs rather than a lightweight racer.
The first Cloudultra was one of my favourite trail shoes, so the new model had a high bar to clear. This review covers fit, cushioning, grip, wet-weather performance and faster running.
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On Cloudultra 2: key specifications
The Cloudultra 2 is an all-terrain trail shoe designed mainly for long distances and ultrarunning. On lists maximum cushioning, a reference weight of 295 g for the men’s version and a 5 mm heel-to-toe drop. The shoe uses Helion foam, a Missiongrip outsole, a TPU Speedboard and a sock-like knitted upper. Source: On.
- Best suited to: long trail runs and ultrarunning
- Drop: 5 mm according to On
- Reference weight: 295 g for the men’s version
- Cushioning: Helion and CloudTec
- Outsole: Missiongrip
- Plate: TPU Speedboard
Weight and fit
I tested an EU size 45, the same size I had used in the first generation. My Cloudultra 2 shoe was 14 g lighter than the Cloudultra 1 shoe I had tested. This is a comparison between my own pairs and size, so it should not be compared directly with a catalogue weight measured in another size.
The shoe goes on much like a sock. Compared with the first generation, I had more room at the front despite choosing the same size. The upper and collar felt more pleasant, and the shoe was comfortable from my first sessions. Fit is personal, however, so I would still test it on an easy run before committing to a long race.
Missiongrip outsole and traction
On redesigned the Missiongrip lug layout and claims 50% more ground contact. This is the manufacturer’s figure rather than my independent measurement. Cloudultra 2 specifications.
I ran on gravel, forest paths, mud, wooden steps, and wet and dry rock. The grip gave me enough confidence on steep descents as well. Occasional slips still happened, especially on more difficult wet surfaces, so I would not treat this shoe as a guarantee of control in every condition.
The Speedboard does not turn the Cloudultra 2 into a racing flat, but the midsole does not feel lifeless. The transition from landing to toe-off felt smooth during both easy running and somewhat faster sections.
Cushioning and ground feel
The biggest difference from the first generation was the softer midsole. The Cloudultra 1 isolated my feet from rocks more effectively, but also felt firmer. The Cloudultra 2 adapts more readily to uneven ground. Rocks are slightly easier to feel, yet the softer foam reduces harsh, concentrated impacts. On longer sessions, I preferred this more flexible character.
Upper and wet-weather performance
Rubber elements around the lower part of the upper help with shallow puddles, but the Cloudultra 2 is not waterproof. The breathable mesh lets water in fairly quickly during rain or after stepping into a deeper puddle. Its advantage is that it dries faster than the denser upper of the first generation.
Can you run fast in the Cloudultra 2?
The Cloudultra 2 is designed for long runs, so I did not expect the feel of a lightweight racer. While returning after an injury, I still ran in it at roughly 4:00 min/km and did not feel that the construction clearly held me back. I would choose a lighter shoe for a short, fast race, but the Cloudultra 2 is not limited to slow jogging.
On Cloudultra 2: strengths and limitations
- Strengths: softer cushioning, a more comfortable upper, a fit that worked well for me over longer distances, and dependable traction on many surfaces.
- Points to consider: the breathable upper gets wet quickly, and rocks are more noticeable than in the first generation.
- Best for: runners looking for a comfortable shoe for long trail sessions, mountain outings and ultramarathons across varied terrain.
Verdict
The Cloudultra 2 improves the aspects I liked least in the first generation. It is softer, more comfortable and slightly lighter in my size. The outsole still feels protective while giving a clearer sense of the terrain. The upper is more pleasant and breathable, although the trade-off is that it gets wet quickly.
For long runs across varied terrain, I would choose the Cloudultra 2 over the first version. If maximum speed or waterproofing is the priority, I would look for a different shoe.
