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Onyx MTB Rear Hub

Average User Rating: (Spectacular) Vital Rating: (Outstanding)
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SPIN FOREVER! Onyx Racing's Silent MTB Hub Review

Onyx Racing hubs spin for so long! This translates to the trail with a sense of free-speed and you'll find yourself coasting for longer.

Rating: Vital Review

There's ZERO noise, too. When you all you can hear is tires ripping into turns it's truly an awesome sensation. You start to pick up on things you wouldn't otherwise notice, like the sounds of your surroundings or that floppy cable you should probably address. Just be mindful when coming up on others and give a holler because you basically come a high-speed MTB trail ninja.

The sprag clutch mechanism inside provides instant engagement with a gently damped feel instead of the slop or clunk you may be accustomed to with a pawl-style hub. In our view, this makes for an altogether better ride experience across a variety of terrain.


Onyx Racing Classic MTB Hub Highlights

  • Ceramic hybrid bearings
  • Patented sprag clutch mechanism
  • Instant engagement and disengagement
  • Silent operation
  • 7075 aluminum alloy hub shell
  • Heat treat hardened stainless steel driver
  • Labyrinth seal between driver and hub shell
  • Adjustable preload for bearings
  • Titanium bolts
  • Multiple anodization/powder coat color options
  • 5-year limited warranty
  • Weight: 473g (16.7oz, claimed) for 12x148mm rear hub with XD driver


Aside from a single easy-to-do preload adjustment, our test set has required NO maintenance during three seasons of continued use when paired with an also-impressive set of NOBL Wheels carbon rims.


Onyx recently released their new Vesper hub in a variety of sizes. This uses similar tech inside but has been slimmed down about 60g (2.1oz) in the popular Boost 12x148mm variety. It has 1.5 sprag clutch rows inside, instead of two, and a common axle design for easier and cheaper driver swaps.


What's The Bottom Line?

Priced in the mid-$400s and up for a rear hub, Onyx makes what many would consider a luxury option. We're believers in the benefits and ride quality of their sprag clutch system, and in our experience things have proven truly worthy in the long run. Here's a big thumbs up from Vital MTB!

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About The Reviewer

Brandon Turman - Age: 33 // Years Riding: 18 // Height: 5'10" (1.78m) // Weight: 170-pounds (77.1kg)

"I like to have fun, pop off the bonus lines on the sides of the trail, get aggressive when I feel in tune with a bike, and really mash on the pedals and open it up when pointed downhill." Formerly a mechanical engineer and Pro downhill racer, Brandon brings a unique perspective to the testing game as Vital MTB's resident product guy. He has on-trail familiarity with nearly every innovation in our sport from the past several years and a really good feel for what’s what.

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7 comments newest first

I got a set of the old Onyx hubs laced to a set of NOBL rims in... 2017? Sold them last year with a stupid amount of kms on them. So smooth, so quiet, so little maintenance. I picked up another NOBL set last fall with the Onyx Vesper hubs and fell in love all over again. I'm honestly thinking about selling a brand new set of RF Vault hubs that were destined for my DH bike and finding a set of Onyx hubs instead. So good.

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There have been other hub makers that have done this. Stealth I think is one. But when put up to use on a trials bike, they just couldn't hold up, which greatly delayed their release. I'm a bit out of touch with the trials scene and wonder if these were tested under such conditions and are they just the new standard and everyone is on them? If they hold up, this is the holy grail of trials hubs.

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in a previous life i've done a lot of hub testing... the sprag designs have their issues... thats why they are not the first choice for freewheels that need to survive a high torque load (like trials) and still be light and low cost... but they do fine on modern 30x50 combos which are pretty much made to torch light aluminum freehubs with pawls... trials tho.. ooh boy... thats torquey on a hub! a lot would depend on rider weight and gearing used... but that scenario, where the rider is putting their full body weight into the pedals, going slow, or not at all to oomph up some technical feature... that would be the most torque you would expect to send through the freehub... the numbers can get quite high... ive never ever seen any media test hubs in this way... but it would be very interesting to do... and not so hard....

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I love my Onyx hubs. Silent, they seem to coast faster than any other hub I have tried and the engagement is amazing. You really notice the engagement on technical climbs, way more control and confidence.

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Sugar Wheelworks here in Portland laced up a set of wheels for me 2 years ago with Derby 35 Carbon rims and Onyx hubs. I couldn't be happier with a set of wheels. I will never go back to a loud freehub, ever, and instant engagement is a treat.

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1 member review

Amazingly quiet with instant engagement

Rating: Featured Member Review
The Good:

Enjoy the sounds of nature / instantly

The Bad:

Heavier than other hubs in its class

Overall Review:

This is a review for the NOBL branded Onyx hub.

I've never been a fan of super loud bee hive sounding hubs. I used to pack my old hubs with extra grease so they would stay quiet for as long as the grease lasted. When these hubs came to the mtb market I had to try them. NOBL offered them as an option for their wheelsets and I pulled the trigger.

First off these hubs are super quiet. There is virtually no noise except for the sound of the dirt crunching under your tires. It makes for a super peaceful outing in the mountains especially if you're riding solo or the trail systems are deserted. The silence allows me to focus on the trail Unfortunately, if you have anything creaky or poppy on your bike it will suddenly be amplified. 

Onyx offers instant engagement with their sprag clutch. More knowledgeable people on the internet have explained how this works so I won't go into it here. Suffice to say it's not a metal on metal feel like perhaps what other instant engagement hubs users are perhaps used to. You lurch forward with every pedal stroke but it feels more like a very, very taut slingshot if I have to describe the sensation. Still, it's a solid feeling and I love the way it rides. 

Another benefit is the super low drag of these hubs. I've spun these in the workstand (yea I know, very scientific) and the hubs take much longer than my regular hubs to stop and will often spin in the other direction. After 2 years riding in them in the PNW in mud/rain I haven't had a single issue with the bearings. They're still running strong. (knock on wood). 

If they're something that could be improved I'd say it'd be the weight. Honestly the weight is in the center of the wheel and I really can't feel it. I think Onyx has addressed the weight with their new lighter Vesper hubs, but I see no reason to upgrade as this is a non-issue for me. 

Conclusion: I love these silent sprag clutch hubs. They've spoiled me and I don't think I can ride anything else. Be prepared to sneak up on people though. You might want to purchase a timber bell as well. 

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11 comments newest first

Very. In depth rebuild videos on their website. Just require a very specific (and not cheap) lube made by Kluber. They will sell you a “single serving” blister packet for cheap or a larger tube if you need. Doesn’t take much per rebuild though.

I would also like to make note of the amazing customer service from these guys. Dan and crew run a fantastic and very transparent business. Responses are always quick, professional, and honest. Small American business that will continue to receive my money and support. Getting ready to order my third set of hubs.

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These are great hubs. The silent clutch makes the V4 Supreme super stealth. Pedaling out of corners always puts down power with the unique clutch system. I'd love to try them on my trail bike someday.

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Ive always loved dead silent bikes and had stealth hubs on my bmx race bikes. but with suspension I've always wanted to ask/know if you've noticed any more pedal kickback or any difference in suspension with instant engagement than standard engagement systems that usually have a little slack?

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Good question. For bikes that have a LOT of kickback, maybe. It depends on how sensitive to it you are, what type of pedals you're running, etc. It will also be more pronounced/audible/noticable on hubs with traditional pawls (ie not Onyx).

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I personally haven’t found it to be an issue, owned on a dh rig and trail bike. The somewhat “soft” engagement on the onyx makes it pretty much unnoticeable and consistent feeling. Whereas a traditional hub with let’s say 5* engagement doesn’t always mean you get 5* of slack for pedal kick. You may get 0 you may get 3*, the later of which I feel like is honestly the worst, that’s when you get the hard catch where you can hear and feel the ratchet/pawl engaging abruptly

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Product Onyx MTB Rear Hub
Riding Type Cross Country, Dirt Jump / Slopestyle, Downhill, Enduro / All-Mountain, Freeride / Bike Park, Trail
Hub Body Material 7075 Aluminum Alloy
Cassette Body Material Heat Treat Hardened Stainless Steel Driver, or Aluminum Driver with Replaceable Steel Pins (+$25)
Rear Axle 12mm x 148mm (Boost)
Bearing Type Hybrid Ceramic Bearings, Adjustable Preload for Bearings
Hole Count 24, 28, 32, 36 Counts Available
Disc Mount Type Centerlock, 6 Bolt
Colors 24 Shell Colors with Additional Widget and Axle Color Options

Shell Colors: Polished Aluminum, Anodized Black, Anodized Matte Black, Anodized Blue, Anodized Gold, Anodized Green, Anodized Orange, Anodized Pink, Anodized Purple, Anodized Red, Powder Coat Black Aura, Powder Coat Black Chrome, Powder Coat Blue Baby, Powder Coat Blue Candy, Powder Coat Green Antifreeze, Powder Coat Green Fluorescent, Powder Coat Green Kawasaki, Powder Coat Orange Fluorescent, Powder Coat Pink Fluorescent, Powder Coat Purple Candy, Powder Coat Red Candy, Powder Coat White Frost, Powder Coat Yellow Cardinal, Powder Coat Yellow Fluorescent

Weight 1 lb 0.7 oz (473 g)
Miscellaneous Patented Sprag Clutch Mechanism
Instant Clutch Engagement During Power Stroke and Instant Disengagement When Coasting
Silent Operation Before, During and After Clutch Engagement
Labyrinth Seal Interface Between Driver and Hub Shell
Adjustable Side Load
Grease Service Temperature Range of -58°F (-50°C) to 248°F (120°C)
Compatibility with Shimano Hyperglide Compatible Cogs

Driver Style: SRAM XD or Shimano
Attach Style: Thru-Bolt, QR, Bolt On
Titanium Bolt
Spoke Tension: 120 Max kgf
Made in the USA
5-Year Limited Warranty
  • $445
  • $470
More Info

Onyx Website

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