Viral Skeptic Review + The Pinion P1.12 Gearbox

With a belt drive, Pinion Gearbox, 27.5+ tires, and an oddly colored titanium frame, the Viral Skeptic might come off as something of a concept bike when it’s clean and shiney. But after a couple months getting it dirty, the sum of its parts equals a rather slick future-proof rig. Read our comprehensive review as well as a detailed look at the Pinion P1.12.

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Viral Bikes — formerly Domahidy Designs — is a Denver, Colorado-based company started a couple years ago by Niner founder, engineer, and namesake Steve Domahidy. Since Steve went out on his own he’s designed and released several small batches of carbon and ti bikes. In 2016, Steve completely relaunched the company with a much more compelling brand name… and an even more compelling flagship bike.

  • Viral Skeptic Review, 27.5+
  • Viral Skeptic Review, 27.5+

Viral Skeptic Review, 27.5+

Given that the first bike under the Viral brand is built around the unusual Pinion gearbox, its name is fitting. Generally, folks are a bit skeptical of anything that breaks from the pack of big brand mountain bikes. And the Pinion is a far cry from the mainstream derailleur-based drivetrains that are specced on 99% of all mountain bikes. As a warning, this was my first long stint with a gearbox drivertrain, so it will admittedly be challenging not to derail this bike review in favor of the Pinion, so let’s jump right in.

Derailed by the Pinion P1.12

It’s no secret that the mountain bike industry’s trickiest quandary is the drivetrain. It’s on an ever-evolving continuum as the two main titans — Shimano and SRAM — perpetually attempt to shift the derailleur system into perfection. This has been especially true over the last few years as 1x took a firm foothold, which was ironically followed by multiple moves to regain the range of the more traditional — but still not that old — 2×10 drivetrain. However, no matter how much they evolve technically, even the most advanced derailleur drivetrains face the same three shortcomings: 1. excessive cog and cassette wear due to variable chainline and jumps between gears; 2. need for frequent maintenance and tuning; 3. the fact that a rear derailleur will always be one of the most damage-prone and vulnerable parts on a modern mountain bike. Aside from spokes and the chain, it’s the most susceptible to mud, dirt and debris. Let’s face it, it’s a fragile mechanical device that’s essentially hanging off the side of your bike ready to be ripped off at will by the next rock or tree branch on the trail. Even more, with cassette rings becoming larger and pushing over 54 teeth, this puts the derailleur lower and in an even more vulnerable position. As bikepackers, we are particularly attuned to all of these potential points of wear and failure.

Pinion P1.12 Gearbox, Viral Skeptic

  • Pinion gearbox, titanium, Viral Skeptic, bikepacking
  • Pinion gearbox, titanium, Viral Skeptic, bikepacking
  • Pinion gearbox, titanium, Viral Skeptic, bikepacking
  • Pinion gearbox, titanium, Viral Skeptic, bikepacking
  • Pinion gearbox, titanium, Viral Skeptic, bikepacking

As the back and forth drivetrain battle ensues, several small and creative companies have been stirring in the shadows, tweaking and reworking internally geared systems that virtually eliminate all three of these issues. The most well known is the Rohloff Speedhub. But, mountain bikers are quick to point a gloved finger its downfalls. Namely, its hefty price tag and the fact that the heavy rear hub throws off a bike’s center of gravity. This is where the idea of a gearbox comes in. It centralizes the drivetrain at the bottom bracket position, technically the heart of a bike’s weight center. Theoretically — for their ability to partially solve the weight distribution issue, as well as upend the common woes of a traditional drivetrain — gearboxes have the potential to overtake the entire industry. I stress ‘theoretically’ but gearboxes do make a lot of sense; they greatly reduce chain and cog wear by removing variable chainline. And by design, they stay in tune. Plus, they eliminate the most fragile appendage on a mountain bike — the rear derailleur. They also allow the use of cheap and reliable singlespeed hubs with symmetrical spoke lengths and tensioning. Not to mention that with minimal annual maintenance they can potentially last a lifetime. This especially resonates in the age of the latest and greatest $400 replacement cassettes.

  • I9 Torch Hub, Gates Belt Drive
  • Pinion gearbox, titanium, Viral Skeptic, bikepacking

Pinion gearbox, titanium, Viral Skeptic, bikepacking

However, the gearbox isn’t without faults, and it would take quite an upheaval for it to gain mainstream success in the mountain biking world. The most promising contender is Pinion, a small German company founded by two former Porsche engineers. And if their resumés are not enough to bring home Pinion’s ‘made in Germany’ cachet, the mind-bending inner workings of their fully sealed 12-speed Pinion P1.12 should do it. To very loosely summarize, the P1.12 is really a transmission. Like Pinion’s other models, the oil-bath shell houses a sprocket array and a camshaft which shifts through 12 unique consecutive positions and aligns the two sprocket groups in a dizzying display of engineering magic. The 12 gears of the Pinion P1.12 deliver a massive 600% gear range. Compared to the 526% gear range in a Rohloff Speedhub, the 500% range of the SRAM Eagle 1×12, 491% from a 2×10 (36/24 chainset/11-36t cassette), and the average 435% range of a 1×11 setup, the P1.12 is unrivaled.

Pinion P1.12 Gearbox, Viral Skeptic

The P1.12 shifts between gears at an increase/decrease percentage of 17.7%. Those are dramatic gaps between gears compared to the 13.6% of a Rohloff or even less on most derailleur drivetrains. This did take a minute to get used to, especially skipping two or three at a time to jump down to lower gears for quick upcoming steep climbs. All the sudden my legs would start spinning like the Roadrunner. After getting used to the step percentage, it was no problem and I quite liked the more consistent and dramatic gaps. Note that some derailleur gaps are inconsistent, especially when considering new cassette expansions and extra-large high gears.

One complaint some folks have voiced about the Pinion is that you can’t shift under load, and that it takes getting used to when coming from a derailleur drivetrain. But, considering that I have a bit of experience with a Rohloff and that I don’t even shift under load with a derailleur system, I had no such adjustment period. In fact, I immediately loved the way the Pinion shifted and thought it was impressively snappy. I found it notably smoother and quicker than the Rohloff, although it works in a similar fashion by way of the twist shifter. Adding to its pleasant usability was the Industry Nine Torch hub specced on the Viral which gave it a quick audible ‘bzzt’ to accent the shift time.

The Pinion has noticeably less drag than a Rohloff. While the gears on the Pinion are spinning, only two are engaged at any given moment. This reduces friction and makes it a bit more efficient compared to the Rohloff, where multiple gears are constantly in contact to produce the gear ratio.

Pinion gearbox, titanium, Viral Skeptic, bikepacking

  • Pinion P1.12 Gearbox, Viral Skeptic
  • Pinion P1.12 Gearbox, Viral Skeptic

As utopian as a gearbox drivetrain may sound, the Pinion still faces two big hurdles in the greater market… weight and price. At 2,350 grams for the gearbox alone, Pinion’s P1.12 is still considerably heavier than the Eagle X01 12-speed drivetrain, or even the Rohloff. And that doesn’t factor in the crank arms, cogs, chain/belt, or the added weight that the mounting plate creates over a traditional BB shell. These bits add up to an additional 600 grams, at least. To compare, the Eagle X01 group weighs about 1500 grams… that’s with everything, chain and cranks included. So comparatively, the Pinion P1.12 almost doubles the weight of the 12 speed Eagle drivetrain. However, Pinion recently introduced the C1.12 which shaves off about 250 grams by way of a magnesium alloy casing.

The price of the Pinion box is complicated. First, you can’t simply buy one. And even if you could, buying a box without a frame would be useless, to say the least. As such, Pinion gearboxes are only sold through bike manufacturers and frame builders. Steve Domahidy points out, “… for me, the Pinion represents about $2,000 of the retail price of the $4,999 frame kit. This includes the gearbox, CNC cranks (which are more expensive), shifter, all of the mounting hardware, a spacer kit for the single speed rear cog to fit on a full-size cassette body, the lock ring tool, and one oil change.” He also went on to explain that the titanium bridge which the Pinion mounts to is an expensive part of the frame. It is a single cast piece of titanium with CNC finishing. Compared to other builders making steel or titanium Pinion frames, “[They] are using a plate and then welding the mounting holes onto that, which to me [for accuracy] is not the right way to do it.”

So if you can get past the weight of the Pinion, how do you get the bike companies to accept it and spec it on their bikes? First, you have to convince the industry skeptics. Although the functionally, lifespan, and trouble-free platform of the Pinion is great, it’s not the perfect gearbox. According to Domahidy, “Nowhere in current mountain bike technology did we demand perfection before acceptance, so it’s a little bit hypocritical to do that with the gearbox. Among others, disc brakes, and both front and rear suspension all went through serious growing pains but are now considered necessary to mountain bikes. The first Manitou suspension fork was little more than aluminum legs sliding on aluminum stanchions with some elastomer bumpers in between, and the naysayers came out in droves claiming it was too heavy, too expensive, and too complicated. The Pinion is much further along in the development cycle than the original Manitou fork was to modern day suspension…”

  • P1.12 Weight (gearbox): 2,350 grams (83 oz)
  • Price: ~$2000 (through frame manufacturers only)
  • Place of manufacture: Germany
  • Contact:

Viral Skeptic Review, 27.5+

Viral Skeptic: The Ride

Of course, Steve saw past the doubters and decided to look ahead with the Pinion, as have several other companies including REEB and Ghost. After spying this bike at Interbike I decided it was time to give it a shot. During the testing window, I loaded it up and took it out for four days on the 350-mile Palmetto Trail. I also rode it quite a bit unloaded on trails around Pisgah and Dupont, my proving grounds of choice and a good mix of steep and technical terrain. While on the Palmetto Trail I had a little bit of a love/hate relationship with the Viral Skeptic. The going was a bit rough. Although there were — quite literally — many moving parts on which to place the blame, I think I owe most my anxiety to the massively heavy DVO Diamond 110/Boost fork. This thing has 140-170 millimeters of travel, and on the not at all ‘all mountain’ Palmetto Trail, it was like bringing a Howitzer to a turkey-shoot. The DVO weighs about 2,100 grams… about a pound over the fork I’d have liked to see on it while bikepacking. And the DVO also doesn’t lock out. That said, when pointed downhill, it was pretty dreamy. It ate up small bumps and cornered as good or better than any fork I’ve ridden to date. But, on flowy trails full of downed logs to hop, with the added weight of a handlebar pack, the DVO fell flat. I will add that had I possessed the patience and knowledge to perfectly tune this complicated beast, things may have gone better.

  • DVO Diamond Fork Review
  • DVO Diamond Fork Review

The Viral Skeptic features a partially polished and partially painted triple-butted titanium frame that’s available in both Brown Sugar and Hot Pink. I really wanted the pink, but Steve sent us the sparkly brown model, and media can’t be choosers. The brown did grow on me though, and would probably be my preference if I was to make a purchase. The large Ti frame weighs about 4.4 lbs (2 kg) and does a really good job of balancing out the added weight of the Pinion. The overall weight of my test bike was 30 lbs (13.6 kg), which is right in line with many trail hardtails with a derailleur based drivetrain. A few other frame highlights include a tapered headtube, a slight curve in the downtube, space for two bottle cages and 12mm sliding rear dropouts. The 148mm BOOST spaced rear-end fits up to 3″ tires. Steve did inform me that the in order to accommodate the new Pinion C1.12, which is cheaper and lighter, but also has a narrower Q-factor and tighter chainline, that they had to lose a tiny bit of clearance in the chainstay. When asked if it could still fit 3″ tires, he assured me that this is no problem and something like a WTB Ranger Plus 27.5X3 on an Industry Nine BC450 would work with room to spare.

  • Viral Skeptic Review, 27.5+
  • Viral Skeptic Review, 27.5+
  • DVO Diamond Fork Review
  • Ranger 27.5x2.8
  • Viral Skeptic Review, 27.5+

The Skeptic features a geometry that’s not unfamiliar from that of other modern plus trail bikes, even though it’s dubbed an ‘all-mountain’ hardtail. Calculated based on a 120mm fork, it features a fairly standard 68° head tube angle, 74° seat tube angle, 435mm chainstays, and 58mm BB drop. Overall these numbers added up to what seemed like a great mix of a highly reliable and pedalable steed, and a nimble trail bike. It was a fun bike to ride, especially downhill, unloaded. And when I was able to get my head past the fork, the Skeptic felt pretty good pedaling over distance. The relatively low BB along with the steepish seat tube kept the bike comfortable and very well balanced over long rides. Truly, I think the geometry and frame specs are almost perfect for what I am looking for in a hardtail, for both trail riding and bikepacking. My only complaint in that regard would be the lack of bottle bosses on the underside of the downtube, which theoretically seem like they could work as there is space.

Viral Skeptic Review, 27.5+, Bikepacking, Revelate bags

Viral Skeptic Build Kit

We won’t spend a lot of time here as the Skeptic is sold only as a frame and Pinion combo. But, I will make mention of a few of the included components and how they affected the test of this bike.

The Pinion was configured with a Gates Carbon Belt drive. I personally have mixed feelings about the belt drive. In dry environments, they squeak. According to others, belts break on occasion; although I had no problem with this one. And they can sometimes feel a tad sluggish, or so I thought. I would like to try the Pinion — and the Viral Skeptic — with a chain. That said, the belt drive is light, stays clean, and doesn’t require chain lube. That certainly adds to the ‘ride, rinse, repeat’ simplicity behind the Viral Skeptic.

The Skeptic was also specced with an array of carbon parts. Atomik handlebars, rims and a carbon railed WTB saddle, which I swapped for my Ergon SMC-4 for personal preference. These were all great and likely helped balance the weight of the Pinion gearbox.

Domahidy also had the wheels built with Industry Nine Torch hubs on the demo bike, which was a nice touch. The quick engagement of the driver and that distinct I9 sound was a welcome addition.

Viral Skeptic Review, 27.5+

  • I9 Torch Hub, Gates Belt Drive
  • Atomik carbon rims, 27.5+, bikepacking
  • Weight (frame): 4.4 lbs (2 kg) (frame only)
  • Price: $4999 (frame and drivetrain)
  • Place of manufacture: Colorado/Germany/Taiwan
  • Contact:


  • Light titanium frame helps offset the extra pound and a half from the Pinion.
  • Solid geometry serves a good balance for trail riding and as well as long days in the saddle.
  • The rugged and durable Pinion gearbox makes for a great long trip trouble-free drivetrain.
  • Pinion P1.12 offers really snappy and efficient shifting as well.
  • The Skeptic is also a really nice looking bike with clean lines and a sparkly paint job.


  • Sluggish on the flats, but this may be more due to the fork specced on this build.
  • Not as lightweight as other titanium hardtails, due to the Pinion.
  • I wish Viral offered the option of a rigid fork.
  • No bosses on the downtube.

Viral Skeptic Review, 27.5+

Wrap Up

First things first, I think the geometry of the Skeptic is spot on for what I consider the ideal bike — a solid trail bike that’s well suited for bikepacking. That basically means a blend of stability and agility. While the specced components were nice, they didn’t mean much in the grand scheme of things, considering the bike is sold as a frame/drivetrain combo. That said, the lightweight carbon rims, handlebar, and I9 hubs all played a role in the demo bike’s handling and ultimately in this review. The carbon bits also helped offset the added weight of the Pinion. While I struggled with the DVO Diamond fork that came with it, I was able to get past it, especially while picking apart downhills with tack-sharp accuracy that surpassed any hardtail I’ve ridden to date. There was a sense of sluggishness that I felt with the bike; I think I owe it primarily to the fork — both its heaviness and the possibility that it was set up with a bit more travel than needed — but in all honesty there could be some added effects from an orchestra of other variables: the weight of the Pinion, a slight bit of drag from the gearbox, and the belt drive.

Shortly after sending back the Skeptic, I started scheming how I could use the Viral Skeptic on another big trip in Central Asia. Between its well-designed titanium frame, the drivetrain and ‘ride, rinse, repeat’ reliability and simplicity, it makes for the perfect exploration rig to take just about anywhere. If you are looking for a trail bike that has the potential for a month long trip through technical footpaths in Nepal, or you are setting out on big rides with plenty of singletrack, the Viral Skeptic might just be the perfect bike.

As far as the Pinion is concerned, I can see a bright future for their gearbox. It’s an impressive piece of engineering. Who doesn’t like the idea of a low-maintenance, worry-free drivetrain. And Pinion is certainly on the frontlines. In addition, Pinion offers a 5-year warranty with the P1.12 and it’s reportedly built to last over hundreds of thousands of miles. But we only had a couple months with the P1.12. I’d like to try the new C1.12 over a longer span and see what it’s like to change cables, add lubrication, and find out how it holds up over a long trial period. We hope to do this in the future and answer a lot of outstanding questions…

Last but not least, while most would consider $5K for a frame/drivetrain pretty damn expensive, Viral offers a lifetime warranty on the Skeptic frame. And with the Pinion built to last for well over 100,000 miles, this could just be the last bike you buy.

Logan Watts

Rider Profile

Between big trips, Logan can usually be found riding his favorite trails in Pisgah, NC, or tacking together 4 or 5 day singletrack-heavy bikepacking trips throughout the eastern US and beyond. He and his wife Virginia recently finished a trip across Cuba. The Viral Skeptic was loaned to Logan for this review.

  • Height: 6’0” (183 CM)
  • Weight: 170 lbs (77.1 KG)
  • Inseam: 33” (83.8 CM)
  • Current Location: Pisgah, NC
  • Favorite Beer: Anything by Burial
  • Favorite Route: Gila River Ramble
  • Joe Maki

    Since the Skeptic is sold as frame and drive train only, a rigid fork would always be an option.

  • Yeah, I would like to have tried one. If for nothing else, to get a feel for the bike without the effects of suspension…

  • Christian

    You stated that there is less drag compared to Rohloff. I have a Rohloff hub myself and sometimes have a nagging feeling that it is not as efficient as I had hoped. I did, however, come across this German test, concluding that Pinion (the 18 speed version) is in fact slightly less efficient than Rohloff.

  • Interesting. Perhaps the idea that it had less drag was in my head. One thing with a Roholff, and I assume with the Pinion as well, is that the drag changes over time. From what I understand, this Pinion has been in the demo fleet since he launched at Interbike. Not that that is a determining factor, but it’s something to consider. The Pinion, without a doubt, doesn’t have the weird noisy gears like #7 in the Rohloff. The Pinion also didn’t have the periodic gear skip that Rohloffs are known for…

  • fauxpho

    Thanks for the detailed thoughts on the Pinion. I’d love to see gearboxes take off.
    I think you need to re-check your math in the references to typical drivetrain gear ranges. A typical 11 speed setup (24/34 front paired with an 11-42 rear) has a 541% range. A typical 10 speed (22/36 up front and 11-36 out back) is 536%. Both far greater than the 435% you noted.

  • Smithhammer

    Excellent review. As much as I can acknowledge to shortcomings of conventional bike drivetrains, I can’t say I’m ready to take the leap to something like the Pinion. I’m no weight weenie, but 6.5lbs, by the time you add in the cranks, etc. is just not worth the upsides to me. Conventional drivetrains may have exposure and some vulnerabilities, but they are also simple and the parts are easy to get to and work on when needed.

    Nice bikestand, btw. ;-)

  • Joe Maki

    Just doing a quick search, there doesn’t seem to be a lot of rigid options for 27.5+ boost wheel sets.

  • Neat, I’ve been curious about that gearbox. Seems pretty sweet. I think the only serious downside is that it looks like an e-bike motor

  • Ryan Smith

    Logan, I’ve heard that the pinion has a torque rating of 250 NM/Watts. If so, it’s tricky knowing your efforts without a gauge, might be a draw back being in the dark. I’ve never heard of someone damaging a pinion in this way yet. Also with the belt drive did you carry a spare belt and tool to measure tension? In the event you had to re-tension the belt for a flat tire…etc.

  • You’re right, I miskeyed that… 435 was meant for a ‘average’ 1×11 (changed)… although that number is a little high — I took into account various mods. Not sure why you referenced 2×11 though… I had not mentioned that in the article. I also added 2×10 which I changed to 36/24 (a little more common, IMO).

  • I didn’t carry a spare belt. I probably should have; definitely would have if it was a larger trip. I have heard that belts often break from getting beat up on logs and such…

  • That it does. I was asked more than once…

  • Thanks!

  • Yeah, I wouldn’t think so. I was ‘wishing’ that Viral would have made one, or contracted out one…

  • fauxpho

    Not sure where I got the 2X assumption/perception . . . maybe because I ride 2X on my bikepacking rig? . . . anyway, with your edits the examples are unambiguous, thanks for listening.

  • I think the 22t is pretty standard with Surly OD cranksets, perhaps there? I ran the same set on my Krampus! Those have great range, IMO. Looking at Shimano it seems like 24/36 is more mainstream though. Thanks for the catch!

  • Christian

    It’s great to have a review where your insights into the Rohloff are included. I agree that Rohloff certainly has its quirks, the noisy 7th gear being one. I have also the occasional gear skip if I accidentally try to change gear in the lower seven under load, but to me it’s a non-issue. I also experience small oil leakages with my Rohloff hub, which seem to be common, but not affecting performance. Some loud gear slipping has been reported with Pinion as well as cranks creaking and falling off. But I guess all new technology needs some dialing-in time. However, as you mention, on paper there are certainly some advantages to Pinion. The ability to easily and cheaply change rear-wheel seems particularly attractive to me.

    I would love to test Pinion on lighter/shorter trips, but for longer stuff in the 3rd world, I would for now stay with the more tested system.

    BTW, have you entirely quit Rohloff nowadays?

  • Hi Christian. Rohloff is definitely the proven option. Recently I have gotten away from it on anything but big trips. That said, my last two month long outings have been on 1×11 setups. Beyond that, pushing three months, I would still rather use a Rohloff or Pinion though…

  • Joe Maki

    I think 1.5 lb over a standard drive train is more accurate. This bike is a little lighter than my Jamis Dragonslayer Pro.

  • Rob H

    From what recall the German Nicolai brand put the rohloff into the cranks in their g-boxx bikes, but they were £3k+

  • Janus

    So this is made in taiwan and costs $5000k for a frame only, meh

  • Andy

    Great review as always – I’ll be curious to see if this and other gear boxes catch on in the coming years. I’m actually most interested in that seat bag you’re using, however. Who is the manufacturer? (Or is this some pre-production prototype you got your hands on?) I’m pretty short and am looking for a small seat pack to use with my full-suspension 29er. Thanks!

  • Brad Sedola

    I did manage to snap a belt. Gen 1, non-centertrack Gates belt on a single speed. The tension on those older cogs had to be very tight. The stock tension was too slack so when hammering on the pedals I’d get a bit of slack that would snap the belt into position when it found the recesses in the cogs. This happened maybe 5 times, all while I was adjusting the tension, where it finally broke. Gen 2 centertrack version has been flawless.

  • Brian Thompson

    Andy, Porcelain Rocket make a great seatpost bag that sits up and can even work with a dropper post on a smaller size frame. It’s called the “Albert”

  • Whoops, I completely missed this message, sorry. That’s the bedrock black dragon:

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