Slightly less adjustable than its rival, the RockShox Zeb Ultimate trumps the Fox 38 with less weight and a considerably cheaper price tag. In fact, this Ultimate version costs the same as Fox’s budget 38 that uses a semi open-bath, rather than the sealed, GRIP damper.

Top-tier Charger 2.1 RC damper with high/low speed compression and low-speed rebound tuning

Like Öhlins’s RXF 38, the angular Zeb gets bonus points for packing a 200mm direct brake mount – this is the kind of stopping power needed with a fork this capable, and this design saves weight on an adapter and longer bolts, as well as reduces faff.

Zeb’s 38mm stanchions slide inside significantly longer bushings, so there’s more overlap compared to the brand’s previous best mountain bike fork offering, the Lyrik. These two things are a big part of RockShox’s improvements in chassis stiffness and resistance to twisting, and the Zeb is clearly stiff enough for the brand to confidently offer a huge 190mm-travel version in 29er wheel size – impressive for a single-crown fork.

The Charger 2.1 RC is RockShox’s top damper and gets high and low-speed compression and low-speed rebound tuning. There’s less external adjustment than the 38 then, but set-up is super-simple, hard to mess up, and works for a broad range of rider weights and styles. Considering the Zeb is cheaper than its main competitors, this Ultimate-level damper is the one we’d recommend too; the split low and high-speed compression is worthwhile, plus there’s a step up in overall performance and smoothness compared to less sophisticated models.

Zeb’s Debonair air spring uses a self- balancing positive and negative chamber with optional plastic air-volume reducers to add or subtract end-stroke ramp-up. It runs significantly lower air pressures compared to the Lyrik, making it more sensitive to exact pressure – one or two psi make a tangible difference to ride height and suppleness, so get an accurate pump for making changes.

On hard-hitting terrain, the Zeb feels fluid, calm and composed. There’s minimal pitching of rider weight when stabbing at hard, repeated hits, and both compression and rebound damping feel well balanced and smooth. Loading the fork hard into compressions and jump faces, the mid- stroke gives up a tad easier than a Fox 38, but it’s also harder to bottom out and access all the advertised travel.

Sensitivity isn’t quite class-leading, which is strange to say after so many years of RockShox test forks being the most responsive to small bumps and superb at absorbing micro-impacts. Whether it’s this subtle reduction in sensitivity (especially compared to the older 2020 Lyrik and its proportionally bigger negative air chamber) or the stiff and precise-steering chassis, we’re not sure, but there’s slightly more vibration at the grips compared to the two most supple off-the- top forks – namely the Fox 38 and the DVO Onyx. Deeper in the travel, control and smoothing of feedback into hands and body, when responding to fiercely repeated hits, is also not quite at the level of Fox’s GRIP2 or Öhlins TTX damper.

The RockShox Zeb Ultimate is super-solid, easy to dial in and well-rounded. Aside from being significantly cheaper, Fox’s heavier 38 just edges it in a couple of areas, with better comfort on the longest runs and a more supportive and seamless feel throughout the stroke. What’s also worth considering is, with RockShox delivering such solidity, the well-sorted Lyrik will still be plenty stiff enough for most (even for top-level enduro racing) bikes and riders and is almost 300g lighter.

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