First Ride: Arc8 Essential Trail Bike pairs Low Weight w/ Enduro Geo

We were lucky enough to be invited over to Mountain Bike Connection Winter in Massa Marittima, Tuscany to check out the latest products and technology from a handful of exciting European cycling companies, and to actually ride some of it on the beautiful, well-maintained singletrack of the Trail Brothers’ network. This first-look, first-ride on the new Arc8 Essential is one of a number of reviews from the event. All photos are credited to Rupert Fowler – Bike Connection Agency, unless otherwise stated.

Arc8 started out as a brand selling open-mold frames, but there’s a bit more to their story than that. They weren’t simply ordering from a catalog and slapping the Arc8 logo on with a fancy paint-job; their co-founder, Jonas Mueller, was in fact the original designer of those open-mold frames. The first mountain bikes to carry the Arc8 name; the Evolve, Essential and Enduro Extra, were all open-mold designs. However, as of 2022, Arc8 is on a mission to distinguish itself, with two all-new framesets that are specific to Arc8 and Arc8 alone. Again, designed by Jonas, but with an all-new suspension platform that has resulted in some seriously lightweight and drop dead gorgeous short-travel mountain bikes.

jonas mueller arc8 bicycles engineer at bike connection

Jonas Mueller presenting the two new Arc8 full suspension mountain bike frames at the 2022 Winter Bike Connection. Jonas previously designed carbon frames in Taiwan for BMC and Bicycle.Engineering, gaining an important understanding of how design needs to consider the practicalities of frame manufacturing.

The Evolve FS, released in May of this year, was the first of those two frames. It debuted Jonas’ flex-stay shock-slider suspension platform on a frame that delivers 100-110mm rear wheel travel paired with a 100-120mm fork, respectively.

Now, Arc8 are ready with a second option featuring that same frame layout with the shock slider, only this one is more trail-oriented. The all-new Arc8 Essential is a 120-130mm full suspension mountain bike rocking a set of geometry figures more commonly seen on enduro bikes but in a seriously impressive, lightweight package; the XT Build we rode weighs a mere 12.2 kg in size medium.

New Arc8 Essential

2022 arc8 essential xt build first ride review

A 230mm x 65mm delivers 130 mm travel, but it can be switched out for a 230mm x 60mm shock for 120mm rear wheel travel

The latest Arc8 to bear the Essential name has very little resemblance to the original open-mold Essential of yesteryear. Gone is the four-bar linkage with its 10 pivots, replaced by a much simpler, lighter suspension design that makes use of flexible seat stays and a shock-slider to guide those flexing stays to drive the rear shock – the very same layout boasted by the XC and Downcountry-oriented Evolve FS. Indeed, the development story of this frame is very closely-related to that of the Evolve FS.

  • Bike: Arc8 Essential
  • Intention: Trail Riding
  • Fork Travel: 130-150mm
  • Rear Wheel Travel: 120-130mm
  • Wheel Size: 29″
  • Frame Material: Carbon
  • Sizes: M & L
  • Weight: 12.7 kg (SLX Build in Size Large)
  • Starting Price: 4,399 € (SLX Build)
2022 arc8 essential trail bike with flex stays slider guided shock

Arc8 say their patented slider is small, light and stiff, but it represents an infinitely long lever, creating an almost perfectly linear-progressive ratio. The amount of friction the slider adds to the entire system is said to be minimal; Jonas says, if you were to remove the slider and hold the rods in your hand, the shock mount tab that slides along those rods would move down along them under its own weight.

We get the impression that the Essential is the bike that designer, Jonas Mueller, is most passionate about. He tells us that he named it as such because, if he was forced to own just one bike, this would be it. With the ability to run 120-130mm of rear wheel travel, paired with a 130-150mm fork, this one slots into the Trail category. But, this is a bike that blurs lines in both directions; the lightest stock build comes in at 12.2 kg, but there’s plenty of scope to build something a lot lighter.

2022 arc8 essential flexible seat stays

Jonas is able to tune progression by changing the angle of the rails that the shock slides along. Similarly, moving the rails up or down increases or decreases the rear wheel travel. Moving the main pivot changes the level of anti-squat in the system.

The Arc8 Essential Trail Bike is a dedicated 29er, and it is available in just two sizes; Medium (465mm reach) and Large (495mm reach), accommodating riders from 160-190 cm tall. The team had originally planned to make a small frame, too, but found that riders as short as 160 cm felt the 465mm reach of the medium frame delivered a very comfortable fit. After consulting with Andreas Gösele, doctor of the Swiss Olympic team and a well known bike fitting expert, Jonas decided a size small was not necessary.

arc8 essential 2 geometry chart

Geometry figures pertain to the 2022 Arc8 Essential with 130mm rear wheel travel and 150mm fork

Arc8 Essential Frame Details

arc8 essential downtube shape reduced surface area

The underside of the downtube is actually slightly aerodynamic, presenting little surface area in the direction of travel. More important than aerodynamics, Jonas tells us this feature also helps prevent the downtube from holding onto too much trail debris when the bike is ridden in very muddy conditions, helping to keep weight down.

The Arc8 Essential frame weighs a claimed 1800g. Arc8 said they wanted to reduce the weight of the Essential frame, as compared to that original open-mold design, without compromising stiffness. They went about that by 1. switching to a lighter suspension platform, and 2. by reducing the surface area, not the wall thickness of the tubes.

They applied those changes in reverse order, however. Before they even turned their attention to the suspension platform, they were able to save over 250g simply by reducing the frame’s surface area. Moving away from the four-bar linkage of the original Essential, with its ten frame bearings and all of the hardware that came along with those pivots, Arc8 were able to save a further 118g. 

arc8 essential reverse main pivot

The Essential’s suspension platform benefits from a reverse main pivot, wherein the chainstays sit inside the seat tube and the bearings are housed in the stay itself. That recessed portion of the seat tube, blocked from view by the stays, is in fact open, so debris cannot get trapped between the stay and the seat tube where it might cause damage. It can however enter the lumen of the front triangle. 

arc8 essential debris drainage hole front triangle

A drainage hole is visible on the underside of the frame; this should allow any water or trail debris to, eventually, exit the frame. Arc8 could have saved more weight by switching to a Press Fit bottom bracket, but they opted to stick with a threaded bottom bracket.

arc8 essential trail bike flat mount brake

The Arc8 Essential runs flat mount brakes on the chainstay, with a maximum rear rotor size of 200mm (requires adapter)

2022 arc8 essential trail bike acros headset internal cable routing

In order to avoid the use of apertures on the headtube for internal cable routing, Arc8 teamed up with Acros to create a custom headset that routes the cables through the headtube.

arc8 essential 2022 bottle bosses full size water bottle and accessory mounting point

The front triangle has space for a full size water bottle, and there’s a second set of bosses further up the downtube that can accomodate accessories like tools and spares for trail side repairs.

tire clearnace arc8 essential 2.6" claimed

Arc8 claim the Essential has clearance for a 29″ x 2.6″ tire; here, a 29″ x 2.4″ Onza Ibex tire is shown

Initial Ride Impressions

2022 arc8 essential xt build first ride review

On the Trail Brothers’ Network of Massa Marittima, I rode the Size Medium Arc8 Essential in the top-end XT build. While the geometry chart you see above pertains to the 130mm/150mm setup, I rode the 130mm/140mm setup. This one retails at 5,299 €. That money gets you a Fox 34 Float Performance fork with Grip damper, a Fox Float X Performance shock, a 160mm (or 185mm) Bike Yoke Revive dropper seat post, a Faserwerk Baslerstab integrated 35mm (or 50mm) stem-handlebar combo, Shimano XT 4-piston brake up front with a 2-piston in the rear, and XT 12-speed drivetrain, Newmen Wheel Evolution alloy wheelset and Onza Ibex 2.4″ tires. It weighs 12.2 kg in size medium.

Setting up the bike was a brief affair. Taking the advice of an Arc8 representative, sag was set to 26%. At 163cm tall, I was fairly concerned the Medium Essential’s 465mm reach would be a stretch too far for me. And, I was right to be. With the shorter 140mm fork, the reach is actually slightly longer than that. At any rate, with the 35mm reach Faserwerk Baslerstab handlebar, the effective reach is 505mm, 25mm longer than that of my personal bike, the Revel Rail. The effective seat tube angle is 76°, delivering an effective top tube length of 596mm.

2022 arc8 essential first ride review out of saddle climbing steep trail

There is a port in the underside of the top tube through which cabling for the shock’s remote lockout could be routed. Credit: Mirror Media.

In the seated pedaling position, the bike simply felt too long. Weight was too rearward-biased, felt most acutely on the steeper singletrack climbs. I felt I had to bend forward more than was necessarily comfortable, resulting in my having to lean on the handlebar grips, rather than simply rest my hands upon them. To be fair, that was with the saddle positioned at the mid-way point along its rails, so there was scope to shunt it forward more to effectively shorten the front end and improve fit that way. Raising the bar higher up the stack, and cutting the bar to a more appropriate width (down from 800mm to 740mm) would have also helped reign in the reach, but i’m not entirely convinced it would be enough to achieve a good seated pedaling position for this 163cm rider.

On the climbs, the compromised fit did make the bike feel less efficient than a bike of this weight and travel bracket should feel. My hip flexors simply don’t have the mobility for that pedaling position to feel good. Having ridden bikes with a considerably shorter reach for many years, my muscles are adapted to pedal most efficiently at angles quite different to the angles permitted by the set up on the Medium Arc8 Essential. Based on that experience, I would have to warn shorter riders off the Essential unless of course they have positive prior experience of pedaling bicycles with that longer reach figure.

arc8 essential first ride review winter bike connection italy

The Arc8 Essential’s 410mm seat tube was manageable with the Bike Yoke Revive 160mm dropper, though only just

On the other side of the coin, I had no qualms with the additional reach when riding back down the hills on the blue-graded flow trails of Massa Marittima. It felt OK, but I certainly wouldn’t have wanted it any longer. Coming up out of the saddle, I immediately felt at home. The 64.5° head angle more commonly seen on enduro bikes was a great comfort, and I had no worries sending the Arc8 Essential down steep, rocky chutes with confidence.

That said, the 35mm reach stem with 800mm bars did make the steering feel a little twitchy and alien to me. The bike’s geometry requires an aggressive riding position; the relatively short rear-end (430mm stays) demands that the rider emphasizes weighting of the front wheel through turns in a bid to maintain traction. 

Smooth, flowing, blue-graded trails were spot on for the Arc8 Essential. I had a lot of fun chasing down other riders on fast, undulating singletrack literred with small, optional, natural gaps. The bike gave me the confidence to hit those features, though I did case several of them. Little mistakes like that went unpunished, with the Essential’s 130mm travel taking those impacts in its stride. My willingness to attempt those features blind is evidence of the bike’s playful character. The bike’s low (BB drop of 40mm), slack geometry and trail-worthy spec make it very capable of some steeper, rougher terrain for the right riders. 

A post-ride inspection revealed I’d made use of no more than 80% of the rear wheel travel, and no more than 80% of the fork travel. Thus, while the suspension set up felt balanced, it certainly wasn’t ideal. There was still plenty of travel left in reserve for bigger hits. Likely, the ride would have benefited from running slightly lower pressures in both the fork and shock.

canyon spectral 125 compared with arc8 essential trail bike winter bike connection 2022

I also rode the somewhat comparable Canyon Spectral 125 at the Winter Bike Connection Event – Credit: Rupert Fowler

At the Winter Bike Connection Event, I also had the pleasure of testing the Canyon Spectral 125 (reviewed here by Cory). I mention it here as the two bikes are very similar in regard to their travel numbers, as well as their head and seat tube angles, and I got to ride them both in the same week on the same trails under the same conditions. I was put on a small with a reach of 435mm (50mm stem), and I have to say I felt it was the better of the two bikes. I credit that to the more suitable sizing of the Spectral 125.

The Arc8 Essential has a very different suspension platform to the Canyon Spectral 125, and that can be felt on the trail. The Spectral 125 had noticeably more pedal kickback than the Essential, something this flat pedal rider is quite sensitive to. I’m not comparing apples with oranges too much here, as both the rear hubs had an equivalent engagement angle of 10°.

Pricing & Availability

In addition to the 5,299 € Arc8 Essential XT build described herein, there is also a more affordable SLX build available which retails at 4,399 €. That fetches you a RockShox Pike Select 140mm fork, a RockShox Deluxe Select+ RT shock, a 170mm travel RaceFace Aeffect 170mm dropper seat post, a Newmen Evolution SL 40mm stem with Faserwerk Rockstock carbon bar, a Shimano SLX 12-speed drivetrain, SLX 4-piston brake up front with a 2-piston in the rear, and NEWMEN Performance 30 wheelset with Onza Ibex 2.4″ tires.

If you’ve a nice custom build in mind, you can also pick up a frameset for 2,199 € with a Rock Shox Deluxe Select+ RT shock and Acros headset and axle.

Arc8Bicycles.com

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Naero
Naero
3 months ago

I’m okay with the propietary slider and flat mount discs. Cables through the headset is a no though. Why do they do this?

CHF
CHF
3 months ago

I don’t get why a tester does not adjust all the things he can(saddle position, shock pressure) before the ride? And although, why compare to bike (canyon) which is not to big for the rider.
I mean it would have been definitely an important notice right at the beginning: „This frame is missing a size small! So if you are 165cm and smaller better look for a mother ride, how about the canyon spectral…“
I would have loved more information and test with someone how fits the frame size. So it is just not very helpful.