The RockShox ZEB and the Fox 38 have jointly led the enduro and freeride suspension fork segment for years, battling it out at every spec level for the title of best in class. Both manufacturers have fine-tuned their flagship models – but RockShox has gone a step further than its rival, Fox.
RockShox gets down to brass tacks
Just one component has survived from the ZEB’s predecessor – the thru-axle. Everything else is new: a new casting, a new triple clamp, additional bracing around the bushing seats, more understated decals and a fork crown that now also houses the bleed valves. The centrepiece of this new edition, however, is hidden inside: the LinearXL air spring unit in a cartridge design. As the name suggests, it is designed to produce a linear spring rate curve. This means that the force required to compress the spring increases evenly throughout the entire travel. Rockshox hopes this will deliver a consistent and predictable ride feel, similar to that of a steel spring. There is, however, a catch: without firm end-stroke progression, the maximum travel is released more easily, and the fork is more prone to bottoming out. This is countered by the so-called ‘ABO’ – a bottom-out buffer that can be adjusted from the outside using an Allen key. Depending on the setting, it absorbs bottom-outs over the final 10 to 17 millimetres of travel.
To make the ZEB run even more smoothly, another exciting piece of technology is being introduced. Each time the suspension compresses, a matrix of small recesses on the stanchions absorbs oil and, as the suspension extends, transports it via the slide bushings, where it is released again. This constant lubrication is designed not only to help reduce friction, but also to enhance durability and allow for longer service intervals. Thanks to the lower friction losses, the tuning of the new Charger 3.2 damping unit is firmer than that of the previous model. This compensates for the lack of natural damping
Rockshox ZEB Ultimate
Adjust first, then drive.
The setup – simple and effective:
Rockshox stays true to itself and relies on the simple low-speed rebound – we think that’s great! Keep it simple. With the numbered high- and low-speed compression settings (5 and 15 clicks respectively), you can quickly find the right setup. A new feature is the ABO (Adjustable Bottom Out) – a mechanical bottom-out protection system with eight clicks. Here, too, there’s a sticker on the fork leg offering recommendations – though, unlike competitor Fox, these are only for air pressure. As always: we found we got on much better with around 10 PSI less than with the manufacturer’s specifications.
Downhill: Direct, sharp, racing-style
In a direct comparison, the ZEB Ultimate feels like a sports suspension: firmer and more responsive. Despite having the right amount of sag, it provides the rider with more feedback. After high drops and hard landings, the ZEB compresses surprisingly deeply thanks to its linear characteristic curve. However, the lack of end-stroke progression can be compensated for. Three clicks on the Adjustable Bottom Out (ABO) were enough. From then on, there were no more bottom-outs – not even when we deliberately tried to provoke them. The more we put the ZEB through its paces on the test tracks, the more we liked it. With its direct and precise feedback, it has a real race-ready character. In the mid-travel range, it delivers more feedback – a characteristic we’d previously associated more with its competitor, Fox. In short: RockShox has given the ZEB more resistance. That’s cool, but it comes at the cost of some comfort, which casual shredders in particular are likely to miss.
CONCLUSION:
The new RockShox ZEB Ultimate is powerful, responsive, offers great traction and is easy to adjust – though it does sacrifice a little comfort in the process. Either way, the ZEB Ultimate remains one of the best enduro forks on the market. BIKE overall rating: 2.3.
In a nutshell:
- Adjustment options: Air pressure, high- and low-speed compression, low-speed rebound, ABO (Adjustable Bottom Out), volume spacer
- Max. disc diameter / weight limit 220 mm / 170 kg
- Riser pipe Ø 38 mm
- Available suspension travel 150, 160, 170, 180 mm
- Weight 2,565 grams
- Installation length 585 mm
- Torsional stiffness / Braking stiffness 37.7 Nm/° / 263.9 Nm/°
- Price: 1,415 euros
How BIKE carries out its tests
Laboratory: Both suspension forks were put through their paces in our test laboratory. As well as weighing, the programme also included stiffness tests.
Practice: To ensure maximum comparability, we tested both forks side by side on identical bikes (Mondraker Foxy). At the Geisskopf Bike Park, we rode the forks on different trails. For the set-up, we started with the manufacturers’ recommendations and worked our way step by step towards the optimum settings.
Laurin Lehner
Editor