DVO Onyx D1 38 Enduro Fork: Tech Info, Impressions & Discussion

After we published our Enduro Fork Test Sessions, DVO notified us that the setup guide on the landing page of the Onyx D1 38 was incorrect. It's been updated since, but what we referenced during the test recommended too much compression damping and incorrect air pressure. It also said there were 28-clicks of HSC instead of the actual 38-clicks, causing confusion.

Since I still had the fork in my possession post-test, I wanted to revisit the Onyx. I didn't do this just to give DVO a better score. I want Vital's review to be credible and my setup to be useful for Onyx owners. Providing additional comments based on an accurate setup felt warranted and necessary. For comparison, you can go read our impressions of the Onyx from the test to see how our setup led to poor on-trail performance. 

Below are details about the Onyx, followed by my impressions. I wanted to start a conversation about the Onyx so current and potential owners can learn more, get questions answered, and provide their own on-trail feedback.

Fork Overview

The Onyx D1 38 is the latest fork to materialize from the minds' of long-time suspension gurus DVO. With a storied history of developing high-end forks and shocks, DVO's first dip into the 38mm chassis realm was executed with methodical observation and intention. It's not just a souped-up version of their popular Diamond trail fork or a variant of their burly Onyx DC downhill fork—the Onyx 38 represents a new era for DVO of creating purpose-designed forks from the ground up.

Highlights

- Travel options: 160mm // 170mm (tested) // 180mm 
- 29-inch only
- 38mm stanchions
- D1 Damper
- SL Air Spring
- External adjustments:
     - Positive air chamber w/ volume spacers
     - Low and high-speed compression
     - Low-speed rebound
- 15mm floating axle
- 44mm offset 
- Axle to crown: 587mm
- Mudguard included
- Rotor size: 203mm direct mount (up to 220mm compatible)
- Weight: 2,616g
- Price: $1,149 USD

The Onyx D1 38 began as a project to develop a true e-bike-capable fork. DVO wanted to do more than just offer a stiffer compression tune or measly setup tweaks to achieve the support needed to withstand the weight and demands of an e-bike.

Beginning at the CSU, an all-new crown uses thicker arms with a dual hollow bore design to improve strength and stiffness while keeping weight within reason. The crown also has an oversized race platform to stabilize the steerer tube during high-load impacts. 

The arch was intentionally reinforced and relieved in certain areas to provide predictable handling without causing deflection or harshness. As forces increase through the arch, it becomes stiffer, helping it remain compliant and comfortable under small loads and traction supportive and controlled during high-force impacts. 

The lower legs are thicker than DVO's other forks to improve stiffness and vibration damping. Extra-long bushing overlap within the lowers further reduces flex and the amount of damping force needed because there is less binding as the stanchions cycle through the lowers. 

Inside the Onyx 38 is the latest version of DVO's D1 damper. It uses their exclusive Compression Bladder System that is now 30% larger than before to increase off-the-top sensitivity and consistency. A new high-flow compression circuit provides support and damping through the middle portion of the stroke but allows for easier compression during fast impacts. There is also a new high-flow rebound circuit to improve the damper's response time during high-speed impacts. Combined, these updates are intended to create supportive damping without any unwanted compression harshness or packing during big hits.

External damper adjustments include high and low-speed compression and low-speed rebound. DVO aimed to widen the range of adjustability to accommodate more riders. This allows those seeking comfort or those riding hard and wanting support to arrive at a dialed setup.

The D1 Damper is paired with DVO's new SL (super light) air spring. Unlike the OTT air spring found in DVO's other models, which uses an externally adjustable negative spring, the SL damper uses a familiar dual air chamber design. This keeps the fork weight down and allows for a broader range of rider weights to achieve a proper setup. DVO says the SL air spring provides great small bump sensitivity with no mid-stroke hammock while ending stroke progression can be tuned via volume reducers. 

Final details include a floating axle and a removable, integrated fender. The Onyx D1 38 is available in Green, Grey or black with travel options of 160mm, 170mm, and 180mm. It is only compatible with 29-inch wheels and has a 44mm offset with a 203mm brake mount. We tested the Grey colorway with 170mm of travel that retails for $1,149 USD and weighed 2,616g.

Helpful Links:

Product Page
Setup Guide 
Service Guide 

What's The Bottom Line?

Here is how my settings have changed from Test Sessions to now:

At 180 pounds, 67 psi gave me 18% sag and landed me within DVO's recommended pressure window. A few psi does make a noticable difference, and it took a few rides of pressure bracketing to end up at 67 psi. I did try less and more pressure, the results being as you'd expect—less pressure (62 psi) caused the fork to dive and ride too deep in its travel; more pressure (70 psi) was harsh. This helps explain why the Onyx felt like it had too much feedback during the test as I was over-sprung at 71 psi.  

Even though the HSC dial has detents as you twist it, DVO recommends counting full rotations from open, NOT closed. During the first handful of rides, I steadily closed HSC to increase bottom-out support and control. With 38 clicks, the change between each detent is small, so it makes sense why DVO says to count full rotations. A rotation equals 8-9 clicks. I settled on 10 clicks, or 1 ¼ rotations, or 28 clicks out from closed. Based on my air pressure, DVO recommends one rotation of HSC. LSC I ran the same as before, at 4-click out of 5, or almost fully open.

The HSC was a real point of contention the first go around because it felt absurd having so many clicks with so little damping change. But if you think of the adjustment as full rotations, there are essentially five HSC positions. Plus, all the clicks in between to fine-tune if you please. I did try tossing on another 10-clicks (~1 full rotation) of HSC which firmed things up, but it didn't improve control during fast, repetitive compressions. It only gave the fork a more jarring wall of support later in its travel.  

DVO recommends between 14-18 clicks of rebound (counted counter-clockwise from closed). I ended up at 21 (25 clicks total). Rebound is a bit of a personal preference, but for me, the Onyx's rebound felt a touch underdamped on my home trails. I tried no rebound damping, and it was still rideable; the fork just started to top out and was skittish enough through rock gardens that I added a few clicks. 

With my new settings, here is how my scores has changed:

I left the 'Support and Stability' score the same because the fork still lacked damping control during fast, deep compressions. When I tried closing HSC, I reached a point of diminishing returns where the fork became harsher instead of calmer. The same thing happened when I tried increasing air pressure to build support. I never reached bottom out too quickly or abruptly, which kept me from adding another volume reducer. I enjoyed how supportive the fork felt during its mid-stroke, and thought the chassis stiffness added control in hectic sections. I just found that when I started hitting back-to-back compressions at speed, the Onyx wasn't as composed. This by no means was a detriment to overall performance, but compared to the Ohlins RXF38 or FOX 38, which were the most supportive in the test, the Onyx didn't offer as much stability.  

Tunability I increased by .5 because DVO's correct setup guide was helpful and accurate. I'd still like more HSC and rebound damping to match my riding style. I also think the number of clicks, the way you count them, and the way you turn the dials can create some confusion. But for most riders, if you take your time and follow the setup guide, an ideal setup can be achieved.

Comfort I increased by a full point because running the correct air pressure made the fork much smoother off the top and compliant during high-frequency chatter. It also allowed me to reach bottom out without the fork feeling too stiff and oversprung. This resulted in better traction, and a planted front wheel through loose rocks. I definitely blamed the chassis for the lack of comfort the first go around, so it's nice to see that wasn't the culprit. The Onyx is on the chunkier side, and I never had to worry about getting tossed offline or the fork deflecting. The downside was my arms fatigued quicker during physical or long descents. 

Traction I also increased by half a point for similar reasons. Conditions have been extremely loose lately, and the fork did a good job fluttering within the first half of its travel, keeping the front tire on the ground through corners and off-cambers. 

Overall, dropping air pressure proved the most effective adjustment to improving comfort and traction while minimizing feedback. DVO's correct setup guide will get riders to a solid setup, and there is a window of adjustability available with external adjustments to fine-tune performance. The Onyx's weight allows it to do a lot of the riding for you through chunky sections. A hold-on-and-pray mentality, if you will. I think that type of authority, matched with its ground-hugging feel off the top, makes it a nice choice for riders on e-bikes, those riding slippery terrain, or those who want a comfy fork that can plow over stuff. If you are seeking support and control when driving a lot of energy through the fork, I still think there are forks that offer more control the harder you ride them.