08 Jul 2020

With huge 38mm stanchions and 160-190mm of travel, the new RockShox ZEB is a whole lotta fork

The not-so-minor details

Product

2021 RockShox ZEB Ultimate

Price

$1,799 AUD

Weight

2,307g

Positives

- Hugely confidence-inspiring chassis
- Incredibly sensitive and supple performance
- Easy to setup and tune

Negatives

- Not exactly a cheap piece of hardware
- 15mm axle seems small relative to the rest of the fork

Flow Reviews The New RockShox ZEB

There’s a bigger, bolder, and more bodacious sheriff in town, and the name is ZEB. Erm, and who exactly is ZEB? Well, ZEB is a brand new long-travel, single-crown fork from RockShox, and it has just bashed down the door of the mountain bike market to announce its arrival in a most unsubtle way.

There’s a new badass fork in town. Bigger than Ben Hur, but markedly smoother.

Pushing aside the Lyrik and the Boxxer, the ZEB comes packing 160-190mm of travel, a hulking chassis that makes the Lyrik look like an XC fork, and numerous damper options. According to RockShox, ZEB is the answer for the riders out there who were asking for a stiffer and more aggressive fork for their long travel e-MTBs and enduro bikes. Now we’ll admit that we weren’t exactly pining for a fork that was more aggressive than the Lyrik. But having ridden the new RockShox ZEB for the past month, it’s become a whole lot clearer as to who and what this fork is for.

Big Tubes

First thing’s first; the ZEB is big. Like absolutely, humongously, mahoosifly, big. Just like the recently released Fox 38, the RockShox ZEB gets enormous 38mm diameter upper tubes. That’s bigger than the 35mm stanchions found on both the Lyrik and the Boxxer. Only the 40mm stanchions on the old Totem were bigger than this. Whoa!

ZEB meets SID. Zeb eats SID.

On that note, if you’re wondering why the new fork isn’t called the Totem, which would have made total sense, it’s because someone at RockShox may or may not have forgotten to renew the licensing rights to that name. Whoops. So the design team had to come up with a new one. The name ZEB comes from the American explorer Zebulon Pike, who first summited Pikes Peak back in 1806. Pikes Peak (where the Pike gets its name from) is a 4,302m high summit that towers over the RockShox global design centre in Colorado Springs. We’ve never ridden if before, but we hear the singletrack descent off Pikes Peak is the stuff that mountain biking dreams are made of, and it’s the sort of trail that the new ZEB is built to thrive on.

Big Travel

The Lyrik and Boxxer seemingly had the bigger end of the travel range covered, but we’re getting the vibe that the ZEB doesn’t really give a flying banana about that. At its shortest, the ZEB comes in a 160mm travel option, and at its longest it has a whopping 190mm of travel. That’s insanely long for a single crown fork!

In much the same way that the 38 muscled its way into the Fox fork lineup, shrinking the 36’s travel window in the process, we suspect the ZEB will do the same thing to the Lyrik. So while the Lyrik is currently available with 140-180mm of travel, we reckon that travel range will narrow now that ZEB is on the scene.

This thing goes up to 190mm with only ONE crown, madness!

All ZEB forks are air-sprung, so there are no coil options at all. And for the most part, travel is fixed – you’ll be able to get the ZEB in 160mm, 170mm, 180mm and 190mm configurations. Should you wish to change the travel, just like the Lyrik and Pike, you can buy a new air spring assembly for $69.95 AUD.

However, there’s a travel-adjustable version too.

Dual Position Is Back

That’s right, RockShox will also have a Dual Position Air option for the ZEB, though only on the entry-level ZEB R fork. Dual Position Air gives you two distinct travel settings in the same fork – 150mm & 180mm – along with a lever on the top of the crown on the air spring side. Flip that lever, and you can raise or lower the fork’s travel by 30mm on-the-fly.

This is an interesting addition, given that travel-adjustable forks (like the Fox TALAS) have largely disappeared over recent years. However, RockShox says the Dual Position Air option is targeted towards long travel e-MTBs, which makes total sense given they’re more likely to be tackling uber-steep climbs, where a lower front end and a steeper head angle are preferable.

Is The ZEB Stiffer?

Larger diameter tubes are desirable from a stiffness perspective, and that’s exactly why RockShox has given the ZEB bigger 38mm stanchions. But you want more numbers right? Good news – we have numbers for you, you lucky reader you! Here’s some lab test data from RockShox, which compares a 180mm ZEB to a 180mm Lyrik, both 29er forks;

  • Fore/aft bending stiffness = 2% stiffer
  • Side bending stiffness = 7% stiffer
  • Torsional stiffness = 21.5% stiffer

So while the ZEB is stiffer under all bending loads, the big improvement is in torsional stiffness. In our experience, this translates to greater steering precision. Really the biggest improvement though is in the fork’s sensitivity while under load. With that stiffer structure, the upper tubes are able to remain more in-line with each other and the lowers. Further helping to keep everything sliding smoothly, RockShox has also built in more bushing overlap into the ZEB. The net result is less binding and smoother sliding, particularly when the fork is under heavy duress.

That Means It’s Heavier Right?

Yes it most certainly is, by quite a bit. Confirmed weight for our test fork is 2,307g with an uncut steerer. To put that weight into context, it’s a full 300g heavier than an equivalent Lyrik, or about 15%.

ZEB is a touch lighter than the recently FOX 38, for those counting grams.

If we’re comparing to the new Fox 38 though, which is the obvious competitor to the ZEB, the weight is pretty comparable. The ZEB comes in 60g lighter than the 38, assuming both forks are using a bolt-up axle.

There’s A New 1.8in Steerer Tube Option

Deep in the ZEB’s spec list is the mention of a 1.8in tapered steerer tube. Shock! Horror! A new standard! Are we about to kiss goodbye the current 1.5in tapered steerer tubes we all know and love so dearly? Well, not exactly.

We were first alerted to the new standard last year at Eurobike, when German brand Bulls introduced a new long travel e-MTB that featured a custom Suntour fork with a 1.8in tapered steerer tube. The theory behind the bigger steerer is that it of course increases front-end stiffness, which is important for a longer travel e-MTB. However, it also facilitates a bigger head tube that, from an aesthetic perspective, integrates more cleanly with huge downtubes of heavy duty e-MTBs.

Yep, the ZEB is available in the new standard. 1.8in for even more hulk.

Don’t worry though, because the 1.8in tapered steerer tube will be an additional option. So you’ll still be able to get the ZEB with a regular, good ol’ fashioned 1.5in tapered steerer. Time will tell if the 1.8in thing takes off, but with RockShox getting behind it, we suspect we’ll be seeing more of it in the future.

It Still Has A 15mm Axle

As beefy as the ZEB is with its chunky alloy crown and 38mm upper tubes, it still relies on a 15mm diameter thru-axle. According to RockShox, while the engineers did consider a 20mm axle for the ZEB; “a properly designed 15mm axle can be as stiff or stiffer than a 20mm axle“. Now we’re no engineers, but that claim does seem somewhat far-fetched, especially when the Boxxer comes with a 20mm axle.

15mm axle only, does nobody need or want a 20mm axle like found on the Boxxer?

Regardless, we suspect RockShox has gone down the 15mm route as it’s is the most commonly used standard in the mountain bike fork world, and indeed Fox has also stuck with a 15mm axle for its new 38 fork. It probably makes a ZEB upgrade a more tolerable proposition, since riders won’t necessarily need a new front hub to go with it. Still, we can’t help noticing how tiny that little axle looks compared to the rest of the fork.

Of course like the SID, Pike and Lyrik, the ZEB does have Torque Cap compatible dropouts. That’s good news if you have a matching hub, as the oversized Torque Cap end caps provide a really solid interface between fork and hub, boosting stiffness further. If you don’t have a matching hub, which let’s face it, is probably most people reading this, then fitting the front wheel involves the usual story where the hub annoyingly floats around in the oversized fork dropouts until you can locate the axle cleanly all the way through.

Testing The RockShox ZEB Ultimate

For the past month we’ve been putting the new ZEB to the test on our home trails. RockShox will offer the ZEB in a variety of spec levels, from the entry-level ZEB R, all the way up to the ZEB Ultimate that we have here. Check out pricing and specs for all the ZEB variants down the bottom of the page.

Our test fork came setup with 160mm of travel and a 44mm offset, and was fitted to the front of a Specialized Stumpjumper EVO Carbon test bike. The ZEB uses 200mm direct-mount brake tabs, so no adapter is necessary when using a 200mm rotor. The fork is rated for use with up to a 220mm rotor though – something we’re increasingly seeing in the DH and long travel e-MTB world.

The ZEB will also swallow up to a 2.8in tyre. Our test bike has a 2.6in Specialized Butcher on the front, and there’s oodles of mud room around the fork arch. And as with the latest SID, RockShox is offering a snazzy new bolt-on mudguard option for the ZEB, though we haven’t been able to try one just yet. Also nice is the new bolt-on hose guide for the front brake.

A neat new detail, the front brake line clamp is tidy.

We’ll point out that the Stumpy is definitely on the more svelte end of the spectrum for what the ZEB is designed for, and indeed it does look comically oversized on there. The Enduro would be a much more suitable platform for the ZEB. Another thing to note is that in addition to different offset and steerer tube options, RockShox will also have large and small crown sizes too. Just to be clear though, this is about aesthetics rather than function. The larger crown option (which is what we have here) is designed to match up more cleanly with frames that have bulkier head tubes – a frame like the Pivot Firebird 29 springs to mind.

Setting Up

The ZEB comes equipped with the newest iteration of the DebonAir spring, which we tested recently inside the new Lyrik and Pike. With the main seal sitting directly on the transfer port at full extension, you don’t need to cycle the fork to equalise pressures between the positive and negative chambers. You can adjust volume via the same grey Bottomless Tokens that the Lyrik uses, and they thread into the underside of the top cap as per usual.

Because the stanchions are so much bigger than the Lyrik though, the air spring volume is a lot bigger too. This means operating pressures are considerably lower, and it also means that small changes in pressure of just 1-2 psi will be noticeable. A good shock pump is a must.

We found the setup to be straight forward, and what we’ve become used to with the current crop of RockShox forks. Nothing new to get your head around here.

To suit a riding weight of 80kg, we set up the ZEB with just 57 psi, which is delivered around 20% sag.

In the other leg is the Charger 2.1 RC2 damper. Functionally this damper is identical to that found in the Lyrik Ultimate, so you get adjustable high and low-speed compression damping, along with a single rebound dial at the base of the fork. Structurally the damper is different though, so it is specific to the ZEB’s bigger proportions.

There’s enough adjustment on offer to fine-tune performance, but not so many dials and clicks as to feel intimidating. Rebound damping was set exactly halfway (9/18 clicks), high-speed compression was set one click from softest (1/4 clicks), and low-speed compression ranged from full-soft to halfway (0-9/18 clicks).

How Does It Ride?

Prior to testing the ZEB, we fitted a current model Lyrik to the front of the Stumpy to get a baseline comparison. For the same given travel, the ZEB sits 5mm taller in its axle-to-crown measurement, so it does bring the front end up a touch.

On the trail, the ZEB is noticeably more stout than its smaller sibling. No, it isn’t a monumental difference, but the ZEB does deliver a more direct connection between your grips and the front wheel, giving the front of the bike a very solid stance. Of course that isn’t always a good thing – a more compliant fork chassis can allow the front wheel to track through chunder, with less jerking on the bars. Lighter and less aggressive riders will still likely prefer the Lyrik, but we can’t say we’ve found the ZEB to be too stiff, it’s a nice balance.

From an Öhlins RXF36 to a Lyrik, to this ZEB, our testing has been clear and concise. More reactive, more confidence-inspiring, but perhaps overkill unless you found a Lyrik lacking.

Helping with comfort and tracking in the rough, the ZEB is beautifully supple off the top. As with the latest Lyrik, Pike and SID, the ZEB is running on Maxima Plush suspension fluid and is fitted with new generation wiper seals made in collaboration with SKF. While the bigger 38mm stanchions increase surface area, and therefore friction, the ZEB is still impressively smooth – a direct result of the increased bushing overlap and stiffer legs, which help to reduce binding as the fork slides up and down.

In the carpark, we wouldn’t say the ZEB feels drastically more supple than the Lyrik. It’s when you’re deep in the travel, with the fork being hammered by successive hits, where it shows its strength. The more robust chassis holds everything in line for longer, allowing the lowers to slide more freely. It’s here where the ZEB is more reactive than the Lyrik.

It’s quite the commanding figure, fitted to the front of a Stumpjumper EVO.

The ZEB’s incredible sensitivity really highlights how far modern air-sprung suspension has come over the years. As an example, we’ve recently been riding a coil-sprung Öhlins RXF36, and the ZEB is vastly more supple. Despite the buttery smooth performance though, the new DebonAir spring keeps the ZEB riding high in its travel, something that RockShox forks haven’t always delivered on in the past. As well as maintaining ride height when pointing down steep chutes, the stronger spring support through the mid-stroke means it’s possible to run less low-speed compression damping in the first place, keeping things nice and active.

It all adds up to a hugely confidence-inspiring front end that tracks really well in steep and rough terrain. On the front of the slack Stumpy EVO, which is capable of some truly raucous speeds, the ZEB delivers true point-and-shoot capability.

Why Not Just Ride A Boxxer?

While the ZEB is super stout for a single-crown fork, it’ll never quite match the strength and steering precision of a dual-crown fork like the Boxxer. And that begs the question; why not just fit a dual crown fork to the front of your e-MTB or long-travel 29er enduro bike? After all, you can get the Boxxer down to 180mm of travel, and it’s only about 200g heavier than the ZEB.

While that is indeed a possibility for some riders and some bikes, there’s no denying the limitations that a dual crown fork places on your bike’s available steering radius. This is something that’s becoming more of an issue with modern carbon frames that are employing huge head tubes, as well as e-MTBs that have similarly huge downtubes. And with more forks moving towards shorter offsets, the issue is even more prominent. All of that increases the likelihood of hitting full steering lock on a tight switchback corner, which can be a total drag on longer and more technical rides.

Of course being a single-crown fork, that’s something the ZEB doesn’t have to contend with, and that’s the key advantage over the Boxxer.

What Bike Is It For?

As good as the ZEB is, it’s still a mighty big fork though. And for many riders, the Lyrik will still be more than sufficient for their rock-smashing needs.

Really the ZEB is designed to shine brightest in its longer travel configurations, and it’s ideally suited to the most aggressive of riders who are taking the truly horrible lines on the most gnarly of EWS courses. Anything less than that, and it’s probably overkill compared to its 35mm stanchioned sibling.

35mm Lyrik vs 38mm ZEB. RockShox is now catering for a new level of brawn.
Big bikes and hard riders need only apply, the Lyrik could suffice for many needs, we’d say.

As such, the bikes that we see the ZEB fitting onto are those at the bigger travel end of the enduro spectrum. You could probably call it Super Enduro. Or perhaps Post-Enduro? Or maybe just Freeride? Anyway, whatever it’s called, we’re talking bikes like the Santa Cruz Megatower, Trek Slash and Pivot Firebird.

It’s also likely to show up on a number of long travel e-MTBs too – the Specialized Kenevo, Norco Range VLT, and Giant Reign E+ would be suitable contenders for the ZEB.

The 2021 RockShox ZEB Range

There will be a variety of ZEB models on offer for 2021, all of which utilise the same 38mm upper tubes, one-piece magnesium lowers, and DebonAir spring. The difference is mostly found in the damper, with the cheapest ZEB R introducing a new Charger R damping unit that simplifies adjustments to a single rebound dial. Prices range from $1,199 to $1,799 AUD, and forks are due to land in Australia in August.

2021 rockshox zeb ultimate

2021 RockShox ZEB Ultimate

  • Travel: 160mm, 170mm, 180mm & 190mm
  • 38mm alloy upper tubes
  • DebonAir spring w/Bottomless Tokens
  • Damper: Charger 2.1 RC2
  • Adjustments: Air pressure, air volume, high & low-speed compression damping, low-speed rebound damping
  • Forged, machined & anodised alloy crown
  • Offset: 38mm (27.5in) & 44mm (27.5in, 29in)
  • SKF wiper seals & Maxima Plush damping fluid
  • 15x110mm thru-axle
  • 200mm direct-mount brake tabs
  • Max tyre clearance: 2.8in
  • Max rotor size: 220mm
  • Colour options: Slab Grey or Ultimate High Gloss Black
  • Optional bolt-on mudguard
  • Claimed weight: 2,281g (29in, 170mm, uncut steerer)
  • RRP: $1,799 AUD

2021 rockshox zeb select+

2021 RockShox ZEB Select+

  • Travel: 160mm, 170mm, 180mm & 190mm
  • 38mm alloy upper tubes
  • DebonAir spring w/Bottomless Tokens
  • Damper: Charger 2.1 RC2
  • Adjustments: Air pressure, air volume, high & low-speed compression damping, low-speed rebound damping
  • Forged & machined alloy crown
  • Steerer tube: 1.5in taper & 1.8in taper
  • Offset: 38mm (27.5in) & 44mm (27.5in, 29in)
  • SKF wiper seals & Maxima Plush damping fluid
  • 15x110mm thru-axle
  • 200mm direct-mount brake tabs
  • Max tyre clearance: 2.8in
  • Max rotor size: 220mm
  • Optional bolt-on mudguard
  • Claimed weight: 2,281g (29in, 170mm, uncut steerer)
  • RRP: Not available aftermarket

2021 rockshox zeb select

2021 RockShox ZEB Select

  • Travel: 150mm, 160mm, 170mm & 180mm
  • 38mm alloy upper tubes
  • DebonAir spring w/Bottomless Tokens
  • Damper: Charger RC
  • Adjustments: Air pressure, air volume, low-speed compression damping, low-speed rebound damping
  • Forged & machined alloy crown
  • Steerer tube: 1.5in taper & 1.8in taper
  • Offset: 38mm (27.5in) & 44mm (27.5in, 29in)
  • SKF wiper seals & Maxima Plush damping fluid
  • 15x110mm thru-axle
  • 200mm direct-mount brake tabs
  • Max tyre clearance: 2.8in
  • Max rotor size: 220mm
  • Optional bolt-on mudguard
  • Claimed weight: 2,270g (29in, 170mm, uncut steerer)
  • RRP: $1,399 AUD

2021 rockshox zeb

2021 RockShox ZEB R

  • Travel: 160, 170, 180 & 190mm (DebonAir) 150/180mm (Dual Position Air)
  • 38mm alloy upper tubes
  • Spring: DebonAir or Dual Position Air
  • Damper: Charger R
  • Adjustments: Air pressure, air volume, low-speed rebound damping
  • Forged & machined alloy crown
  • Steerer tube: 1.5in taper & 1.8in taper
  • Offset: 38mm (27.5in) & 44mm (27.5in, 29in)
  • SKF wiper seals & Maxima Plush damping fluid
  • 15x110mm thru-axle
  • 200mm direct-mount brake tabs
  • Max tyre clearance: 2.8in
  • Max rotor size: 220mm
  • Optional bolt-on mudguard
  • Claimed weight: 2,279g (29in, 170mm, uncut steerer)
  • RRP: $1,199 AUD (DebonAir) – $1,399 AUD (Dual Position)

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