Words by: Liam Woods
There is a new category in mountain bike suspension forks which many are calling super enduro and RockShox and Fox have jumped up their fork options to include these longer travel forks in their lineup. The RockShox ZEB and Fox 38 are the newest forks from both brands that feature 38mm upper tubes, these forks are made for the burliest trails, tested and developed with the world’s fastest riders. We have a full review and video on the Fox 38 as well as a review and video on the RockShox ZEB if you want to really get in depth about each product. In this article, we are going to discuss the similarities and differences between the two. As bikes and tracks are getting ridden harder each year, it seemed like an improvement was due. Stiffer forks not only help create less deflection on trail, but also less binding. This ultimately leads to a smoother feel throughout the travel on small and big hits.
To be fair, these bigger forks are not necessarily for everyone. Both brands are really only making them in 160-180mm travel range which is mostly suited for larger riders above the 200lbs mark or people who ride hard and really don't care about weight and want all the downhill performance they can get. Rockshox and Fox still offer the Lyrik and 36 respectively and those are still the best options for 150-160mm travel range or for riders that might not need the added weight and stiffness from the 38mm forks. Riders like Sam Hill and Richie Rude were some of the top pro’s riding these forks before they were released. As some of the top enduro riders in the world, if these forks are good enough to win races against the fastest riders on the hardest tracks, I think they are plenty good for us average folks.
First is price. The RockShox ZEB retails for $999 for the top level Ultimate tier, while the Fox is a bit more expensive at $1199 for the Factory tier. That right there is a big difference and will be the deciding factor for many riders looking to upgrade.
While many of the features between the ZEB and 38 are similar, both forks have been aimed at the same style of riding with the same end goal, of course there are some differences as well. To start, each brand has their own compression and rebound damper that is much different in the way that it is tuned. The RockShox ZEB has the Charger 2.1 RC2 damper that features independent HSC and LSC with HSC having 5 clicks and LSC having 16, but only one single rebound adjustment with 16 clicks. The Fox 38 has the Grip2 which has plenty of adjustment with 22 clicks of HSC and LSC, as well as independent HSR and LSR with the HSR having 8 clicks and LSR having 22. For many riders, the RockShox will be a little easier to set up but not quite as tunable as the Fox Grip2 damper.
Another significant difference between the forks is the travel and offset options. RockShox has decided to make the ZEB go up to 190mm of travel, a huge travel option for a single crown fork, while the Fox 38 tops out at 180mm for both 29” and 27.5” wheels. While 190mm might be the outlier, it's worth noting that it can go up to that much travel. The offset options is also a hot topic right now, with Fox offering two options in both 27.5” with 44mm and 37mm offset options, and 29” with 51mm and 44mm options. RockShox made a bold move in 29” by only having one offset option at 44mm, while having the two in 27.5” of 44mm and 37mm. I am not totally sure why RockShox opted out of the 51mm, but I would assume they did the research of how many 51mm have been purchased as well as most new long travel trail bikes all ebing spec’d with the new short offset fork options and if you want a 170-190mm 29” fork you are most likely going to use the short offset version anyways.
Last but not last, we cannot overlook the use of air bleeders in the lowers and both brands take on fork axles. Fox has had air bleeders on their Fox 40 for some time now which are designed to help release pressure built up in the lowers during riding as they collect air. This possibly helps when changing elevation but I have heard both sides, some say it works, others don’t. Nonetheless, Fox found it was needed to add to both the new 38 as well as the new 2021 36 fork. It's also worth noting that you will not find these on the RockShox ZEB. Either RockShox does not think it's needed, or there might be some patent pending keeping it out of reach for RockShox, again, not 100% sure on that. What I am sure of is, both brands take the approach to their axles very differently. RockShox uses a more traditional 15mm axle style, but you have the option to use TorqueCaps on all RockShox forks. TorqueCaps are an amazing and easy upgrade to your front end to help increase the wheel to fork contact surface to improve stiffness and steering. The TorqueCaps increase the surface area to 27mm, making them cover more surface area upon contact than old 20mm trail style axles. TorqueCaps end caps are available for many hub options and are not only compatible on the new ZEB but also the Lyrik, Pike, and new SID.
Fox does not use TorqueCaps as it’s a RockShox only feature, but they also have their own take on the axle. While still using a 15mm axle, Fox has dropped the floating axle style from their Fox 40 into the 38 and 36 forks. The floating axle allows you to tighten down the wheel in the fork without binding the two lower legs together. You basically tighten down the axle to the wheel but it floats through one fork leg, you then have a clamp on the fork leg that tightens the axle to the other fork leg. This allows the fork legs to remain parallel between the two. Fox thought that when the fork legs got tightened together there was too much binding, that then makes the fork slightly skewed and can cause binding therefore creating friction in the movement of the fork. Lots of nerd stuff going on with these axle features. Much of which us average riders might not notice, but the beauty is the pro’s do and that technology makes it down to allow us to ride products much nicer than we deserve.
RockShox ZEB Specs:
Fox 38 Specs:
Long story short, both of these forks feel absolutely amazing. The Fox 38 and Rockshox ZEB both take a huge performance gain over their now little brother variants, the Fox 36 and RockShox Lyrik. Over the little brother options, the super enduro 38mm forks feel more planted, more controlled, and what I noticed the most, was the ease with which the forks got into their travel. They both seem to be very smooth off the top with great support. I think much of that is due to the stiffer chassis having less friction and binding through the fork allowing it to just work better and create a smoother feel.
Now to compare the Fox 38 vs RockShox ZEB, what we have all been waiting for. And to be honest, you might be disappointed, both forks are absolutely amazing and it's very hard to pick anything one does better than the other. Both forks are made by the two best suspension brands in the industry. I really have to nitpick the differences between the two, and some of it comes to set up and ease of set up. I think the RockShox ZEB is a bit easier to get set up and feel good. It has less settings, and I found that the recommended air pressure was very close right off the chart on the fork. The Fox 38 has more settings to get dialed in, both compression and rebound, and I found that for a lighter rider I ended up slightly under the recommended pressure on the Fox chart. If you are a rider that loves to get into small setting differences and really getting the fork tuned in, the Fox 38 has more options and would be better for that. If you are the easy set up and set and forget type of rider, then the RockShox ZEB is more your style.
The on trail differences are even smaller between the two, and for my riding weight at only 155lbs, some would argue that I am even a bit too light to justify riding either of these forks, but that is why we also get some of our riding buddies who are on the other side of 200lbs from me to also get their opinions. The Fox 38 seems to handle some of the big hits just a little bit better, the 38 remains composed under multiple hits back to back. This isn't to say the ZEB can't do that, but the 38 just feels smoother and more under control in these situations. The ZEB I think lends itself to be a bit softer off the top and might be better for some riders who choose to ride either of these forks but are a bit lighter.
Since there aren't too many differences on trial to point out, let's talk about what they both do extremely well. Both forks both sit up high in the travel and do not dive too much under braking or steep sections. Both forks also handle chunky sections well as you would expect, but what you notice more than the overall stiffness is how much more controllable the forks are, as there is less flex and less deflection helping you keep your line just that much better.
Super Enduro? The RockShox ZEB and Fox 38 create a whole new suspension fork category made for the longest travel bikes, going down the roughest, steepest trails. With riders like Richie Rude and Same Hill helping in the development of these forks, it's no doubt they are as good as they can get. With 38mm upper tubes, these forks are stiff, smooth, and can handle anything us normal riders throw at them. With little differences between the two, the biggest difference we think is price, with the RockShox ZEB at $999 and the Fox 38 at $1199 for the top models, the rest is pretty similar. What would you choose?
This article was written / authored by Liam Woods. Liam has been in the bicycle industry for over 10 years as a racer, professional mechanic, service manager and as of late, media and content creator. Liam has ridden thousands of different bikes, ridden countless components, tested endless MTB apparel of all kinds and written reviews on it all. He's a key piece to the Worldwide Cyclery "All Things MTB" content creation puzzle. He also makes consistent appearances on the Worldwide Cyclery YouTube channel and Instagram.