John likes to review a carbon full-suspension bike at least once a year to challenge his opinions on his preference of chassis material, and this summer’s bike is the 2024 Rocky Mountain Instinct. Thanks to new geometry, details, and a simplified RIDE-4 adjustment, the Instinct proved to be a very capable 140/150 trail bike. Perhaps the bigger picture of this review is John’s ever-questioning of his quasi-religious, cult-like zealotry for metal bikes…

“Belief is the death of intelligence” is a tenet in Robert Anton Wilson’s Cosmic Trigger: The Final Secret of The Illuminati, an atheist metaphysical Discordianist manifesto that suggests that religious fervor and myopic perspectives degrade both the individual’s and the population’s ability for critical thinking.

As such, I feel like many of society’s most energetic and passionate personalities fall well within the bounds of a “Cosmic Trigger” cult leader – even in cycling! Opinionated archetypes attract followers, and in today’s narcissistic and self-promotional world, the people with the loudest opinions often attract the deepest fanbases.

Without going too much more into this, it’s why people still quote underbiking “gravel” pioneer Jobst Brandt to this day and why Richard Sachs, Grant Petersen, and Jan Heine have long provoked such intense debate within various cycling circles with their rhetoric and opinions on cycling. I might add that I agree with a lot of their opinions. :-)

Ping your favorite YouTube or social media influencer’s latest hardline opinionated rants, and you’ll see lots of passionate commentary from their fans. Everyone has a hot take, and you’re gonna love it!

My favorite science fiction series, Dune, paints a cautionary tale warning society against the idea of ideological messiahs, emotionally powerful leaders, and so-called “great men.” Paul Atredies is not a hero, not a chosen one; he is the villain.

Yet there’s a lot to be said for questioning one’s beliefs in an attempt to gain perspective and, thus, a better understanding of what drove us to such dogmatism! I want to adapt, not adopt, my opinions and perspectives toward cycling vis a vis, questioning the very reasons why I formed them in the first place.

To quote Richard Sachs here, “ATMO.”

Metal Fan

I’m a fan of metal, both in music (derp) and as a chassis material, and it’s been really fun to ride various metal full-suspension bikes. I believe metal full-suspension mountain bikes offer a connected and considerate trail riding experience. My interest lies within sustainability; how long will the frame be on this planet, under the body of some-body, and not in a landfill? If it cracks, is the frame repairable? And finally, steel/ti/aluminum frames just ride differently.

Wait a second. Am I beginning to be too dogmatic? Is loyalty to my deeply held opinions superseding the desire to learn and lessening my life experiences?

Yes, probably.

Doesn’t the world need fewer hyperbolic and binary opinion sets, particularly in media?

Absolutely.

Instinctual Gravitation

After Morgan’s Rocky Mountain Element C70 review, my interest in the brand’s new offering in 2024, the Instinct, was piqued. I wanted to test my devotion to metal bikes while checking out a flagship trail bike from a brand like Rocky Mountain. Its team puts a lot of thought into its bikes’ pedalability and prowess on rugged terrain. The new Instinct claimed to be a “quiver killer,” offering an even better ride experience than its predecessor. Marketing jargon? Perhaps. But I wanted to try the forbidden fruit.

The Instinct seemed like the perfect trail bike for my local trails. 140/150 mm travel delivers the tunability for our primitive and tech terrain while offering a super pedally “from the door into the backcountry” platform.

A rocky trail, Rio En Medio, in the Santa Fe National Forest always keeps you honest… and is a true test of a bike’s and rider’s ability.

My Murmur, with its 140/160 mm travel numbers, has proved to be quite an ally in these summertime exploits here in the Southern Rockies. So, it felt fitting to take a Rocky Mountain bike, designed in BC, into the terminus of the Rocky Mountains here in Santa Fe. The Instinct had my name on it.

I took delivery of the bike this spring and have been riding it into our backcountry terrain as the snow melted, inspired by the brand’s touting of the Instinct as an “all-day exploit” bike.

Reflection and Reflex

Seeing Margus Riga’s photos of the bike in the BC backcountry used in the marketing images inspired me to ride the Instinct on big, hard, solo outings this spring once the upper mountain trails began to thaw from snow. These first rides of the season are always physically and mentally demanding for me. I try to take the winter months easy and allow space for my body to heal from aggressive riding patterns in warmer seasons. Instead, I focus on core-building exercises at home. But that means that come springtime, I am out of riding shape.

On one particular early spring ride, as I ascended into a cloud-covered Atalaya mountain, the caramel scent of Ponderosa pine filled the air, briefly offering a distraction from lead-like legs, an elevated heart rate, and shortness of breath. I cracked multiple times, walked sections, and pushed onward and upward while stopping to take in the flora and fauna emerging from winter slumbers, sharing in this awakening.

Like Moses and the Burning Bush, I had a number of personal revelations that were perhaps only possible through the vulnerability found on big, hard solo outings. It’s easy to conflate exposure and the resulting flooding of endorphins with divine intervention or speaking to the godhead. Yet something was speaking to me. Mountain magick.

There’s something about riding a mountain bike in inclement conditions that gives it such a high spiritual fortitude.

I think it’s also why people get addicted to ultra-racing and eke themselves to the edge of the human experience. These efforts teach us more about ourselves and the reality we inhabit for this brief moment; a falling leaf on a windy day is but a blink within epochs. Whoaaaaaaa.

I’m getting too metaphysical for a bike review, and I’ll end this unnecessary essay with one last note. As Paul Shepard expounded in Man in the Landscape: A Historic View of the Esthetics of Nature:

“To the desert go prophets and hermits; through desert go pilgrims and exiles. Here, the leaders of the great religions have sought the therapeutic and spiritual values of retreat, not to escape but to find reality.”

We’re not in the desert here in Santa Fe, but the feelings we experience on hard, solitary outings are a vehicle for truly discovering our subjective reality.

Ok. I’m done. Let’s dig deeper into the Instinct.

Rocky Mountain Instinct C70 Shimano Quick Hits

• Intended use: Trail
• Taxonomy: In between the Element (down country) and the Altitude (enduro racing)
• Travel: 150 mm front, 140 mm rear
• Wheel size: 29er (S-XL) or 27.5″ (XS, S sizes)
• Chassis: Carbon as reviewed here; aluminum also available
• Sizing: XS, S, M, L, XL
• RIDE-4 Geometry tuning: POS.1 – POS.4 options, flip chip at dropout, and +/- 5mm reach adjust
• Build kit options: From high $10,499 SRAM C99 (carbon) to low $2,899 Instinct A10 Shimano (aluminum)
• Weight as shown: 33 lbs with pedals, bottle cage, and PenaltyBox bag (empty of tools).
• Priced as reviewed: Instinct C70 Shimano $6,499

Run the Numbers and Sizing

As a 6’2″, 190 lb human with long arms and an 81 cm saddle height, I fell right into the size XL without any hesitation. My “extension” fit number – from the tip of the saddle to the bar clamp at the stem – is 55 cm unsagged when set up for riding. The Instinct utilizes RIDE-4 with POS.1 through POS.4 adjustment, with POS.1 being slack and POS.4 being steep, slightly altering the bike’s geometry. For simplicity’s sake, I primarily rode the bike in POS.1, after experimenting with the other positions, so I’ll be discussing those metrics.

The Instinct shipped to me in POS.3 with the flip chip at the dropout in the 440 mm length and the headset reach adjust at 0 mm. 

With a wave of a magic wand, Rocky Mountain engineered the same head and seat angles, rear center, and bottom bracket drop across all sizes of the Instinct (29er).

I try not to look at geometry numbers before testing a bike other than reach to determine my size. But I was shocked to see the seat tube angle at 76.5º when I was sure it had to be at least 78º. I was confirmed in my head tube angle assessment of 63.5º, which I “felt” was around 64º after a few rides.

The rear-center is indicative of the Instinct’s flip chip at the dropout, allowing to adjust between 440 or 450 mm. Again, I kept it on the shorter end for the majority of this review period. After trying it out at 450 mm, I liked the shorter rear end for our terrain more.

Belief in Question

“Do you have a motor in that thing?” said one of my riding mates as we pedaled up a particularly gut-punch of a climb on a long Sunday morning ride. I took a high-consequence climbing line, normally reserved for end-of-season fitness that day, and spun up sections of trail I often walk this early in the riding season due to the steep, loose terrain… and lack of fitness.

“Damn it,” I thought to myself. This is too easy.

My thoughts while riding the Instinct had been very damning to my riding ego, and perhaps the lowest hanging fruit of this realization to speak to first came down to tire size. So, let’s pluck the apple and get into it.

Throughout the review period, I kept coming back to the tire size specced on the Instinct (2.4″ front and rear Maxxis Dissector), which was the Macguffin to this enlightened riding experience. 2.4″ rubber just rolls more efficiently on climbs and is akin to a surgical cut on descents. What your ride quality loses in terms of traction from switching to a smaller tire and, thus, footprint, the Instinct’s suspension platform made up for.

I swapped on my 2.6″ rubber of choice to the Instinct and found it to be less than ideal, losing some of the above-described qualities, and it felt like too much tire. I lost the ability to slice through lines and course correct with minimum input. Climbing also felt “heavy-legged” – I ought to note that these same sensations were mentioned in my Cotic FlareMAX review.

Emotionally, smaller tires feel faster, and numerous personal records broken throughout this review period on very familiar trails made me believe that perhaps my 2.6″ subjective reality-based zealotry had taken away from my riding experiences. I smashed my time on a favorite tech descent in town from the top of Atalaya back down, landing me #10 in the Strava boards. You drop 1,800′ in three miles. This is a trail I ride weekly.

My plan is to swap 2.4″ tires onto my Murmur and experiment with this notion further.

My first fervently-held reality had been questioned.

As Discordianism touts:

“With our concept-making apparatus called ‘the brain’ we look at reality through the ideas-about-reality which our cultures give us.

The ideas-about-reality are mistakenly labeled ‘reality’ and unenlightened people are forever perplexed by the fact that other people, especially other cultures, see ‘reality’ differently.”

My “culture” had been aligned with bigger tires = rowdier riding. Yet I’m finding that not to be the case. If my new revelation were actually true, it would rely on the foundation that suspension kinematics equate to better traction and override the need for bigger tires.

Notes While Riding: Second Revelation

Coming from a simple single pivot paired with a coil shock on my Starling Murmur, to a modified single pivot with an air shock on the Cotic FlareMAX, and right onto a Horst Link with an air shock on the Instinct, I noticed the bike’s immediate “calm and centered” disposition. Cornering on a particularly steep, off-camber, bench-cut descent in the middle of a monstrous climb where many people wash out on the loose corner, I had a revelation…

“This bike is incredibly calm and planted.”

The Instinct climbs like a calm wind blowing willows on a riverbank. During riding situations like this, I’d rely on my bigger tires at comedically low pressures to provide traction while noting that coil-sprung single pivots are inherently more “poppy” and “aloft” two characteristics not linked intrinsically to easily traversing the above-described terrain, nor would I consider the platform feeling “planted.”

I began tweaking the Instinct’s geometry through the POS.1 through POS.4 adjustments, doing hot laps on my favorite section of trail, which included steep, technical climbs and fast, flowy descents with intermittent granite and quartz chunder interruptions, running through each of the geometric opportunities.

While I liked the steeper seat angle and higher bottom bracket of the POS.3 and 4 chip position, I couldn’t get enough of the slightly slacker seat and head angle paired with the short rear end and lower bottom bracket of the POS.1 configuration.

I’m not hyper-pedantic about geometry tweaks, but even I was looking forward to noticing these geo tunes and being bowled over by the bike’s “adaptability.” Unfortunately, I wasn’t and preferred the geometry configuration of POS.1.

Once the suspension was dialed and I wholeheartedly committed to POS.1, the revelation occurred. I began to notice more nuances in the frame’s riding qualities, particularly when charging down rocky terrain.

Metal frames, for me, provide a very smooth and flexy ride quality that not many carbon bikes possess. Instead, carbon bikes tend to feel chattery and have a heavy “trail resonance” to the feel of the frame, regardless of suspension setup, tire pressure, or geometry. There’s also this hollow and vapid feeling to the ride quality when dancing through tech terrain at high speeds.

I think these differences are even more pronounced on drop-bar carbon gravel road bikes than on full-suspension bikes, where the characteristics can be muddied by suspension and tire selection.

Yet the Rocky Mountain team, with their size-specific carbon engineering, developed a chassis that is both flexy in the right ways yet still able to be handled with precision. While seated on the bike, you can press in from side to side and watch the bike twist. It’s amazing.

A good analogy for why I prefer a flexy bike is cutting vinyl with an X-acto blade. When the blade is upright, it slices cleanly in a straight direction, almost guided by some divine force, but adding weight to either side of the blade allows you to carve smooth curves with finesse. You’re not steering the blade like a box cutter but bending the blade to guide its path. X-acto blades are an artist’s tool. A box cutter is a utility knife meant to slice through material in a straight line.

Be the artist in all things.

This is how my favorite steel full-suspension bikes ride.

For me and my riding style, a bike ought to carve smoothly with limited input, not abruptly, resulting in a jarring riding experience. Plenty of carbon bikes feel lifeless or utilitarian, and in this way, they lack artistry. I grew tired of them resonating on a similar vapid wavelength. I never felt a connection to full suspension bikes. Not like a metal hardtail. Then in April 2019, the Starling Murmur was the first full suspension bike that I rode that felt like artistry.

I was surprised wholeheartedly that a carbon bike was muddying my perspective here. The Instinct felt artistic in its ride quality. While it’s made from carbon, the ride quality is akin to a flexy metal bike.

It allowed me to use my instincts in riding terrain that I could navigate blindfolded – okay, maybe that’s a stretch. It’s honestly the first carbon mountain bike I’ve ridden that embodies the snappy, responsive, and smooth traits I’ve come to love with steel bikes.

… and dammit, it’s very hard to admit that.

In my riding notes, I described the Instinct’s ride qualities as:

“calm, planted, and supported while climbing”

“surprisingly flexy and smooth while descending the steeps, able to course correct without descending like it has a mind of its own”

“the rear end flexes nicely!”

“endless traction and control through corners and off-camber sidehill”

“not as lifting or lofty as the Murmur in jib lines but better balanced and predictable”

To explain these sensations, let’s look at the kinematics.

The Reeb SST Horst Link (left) with a trunnion shock versus the Instinct’s Horst Link (right)

Suspension Kinematics

Rocky Mountain’s engineering team kept the same Horst Link design as the predecessor Instinct.

What sets a Horst Link apart from a single-pivot is the ability of the wheel to travel along the axle path while isolating the braking forces from the main pivot, which results in less anti-rise – or the tendency for the bike to pop up during hard braking – versus a non-isolated brake attachment found in other suspension designs.

Rocky Mountain’s design has the lower pivot directly mounted to the frame in a pivot above the bottom bracket in the main link, with a pivot point at the rear dropout and the upper linkage mounted to the top tube and shock lowers. This four-bar system might feel dated in an era with more complicated systems, like that Druid V2 that Travis lauded so much, but the Horst Link remains a tried-and-true platform. If ain’t broken, don’t fix it.

TL;DR: The Horst Link allows the rear suspension to stay more active during braking; usable travel increases while maintaining a progressive feeling and results in a noticeably increased support. However, it also loses some of that jibby and lofty feel found with the more catapult-feeling single pivots.

The kinematics being familiar, I began to admire the small, clever details on the Instinct’s chassis.

Frame Details

Rocky Mountain modified its adjustable Ride-9 upper linkage positions from the previous model Instinct to RIDE-4 (POS.1 – POS.4). Less is more, as the homie Mies says. The lower linkage guard keeps things moving smoothly and is embossed with the Canadian maple leaf. There’s even a flip-chip in the rear dropout to modify the rear center/chainstay length.

I like in-frame storage for items you don’t need to access on every ride. The Instinct features Rocky Mountain’s PenaltyBox 2.0™ is what I would consider spacious. There’s a custom tool wrap and a plastic door that securely latches down, allowing you to mount a water bottle – our Expedition Bottles fit nicely on the size XL. There’s even a built-in concealed AirTag/Tile compartment for theft prevention. The headset has built-in +/- 5 mm adjustability with separate cups, allowing you to tune the extension for a proper fit.

Shipping Damage

I feel an editorial obligation in the interest of transparency to note that when I received the bike, it came out of the box damaged with a broken non-drive-side seat stay. The frame was wrapped with thick foam padding.

The box itself showed evidence of the impact it had undoubtedly endured during shipping that lined up with the frame’s damage. Rocky Mountain sent out a replacement swingarm segment, and the broken piece was swapped out for a fresh one, torquing the linkage bolts to spec as per the manual.

Rocky Mountain has spare parts available to support all its models.

Nitpickin’

A lot of our backcountry riding is on narrow, bench-cut trails. This makes for an abrupt sidehill, and on bikes with lower bottom brackets, an increase in pedal strikes. Through tinkering with the RIDE-4 positions, offering “slacker” to “steeper” adjustments, I discovered that POS.4, with 32 mm of BB drop, slightly eliminated pedal strike on sidehill roots or rocks, but it also drastically altered the descending prowess of the bike… or at least I felt it did.

In the end, I chalked this up to why the Instinct descended so planted and smoothly and was able to lock the rear shock out on climbs to all but eliminate pedal strike. I never found myself striking while climbing or descending rock gardens, however. Only on sidehill, bench-cut trails. Bikes are all about compromises, and through my review period, I found this to be a minor inconvenience. Still, it’s worth noting.

Indoctrinated and Instinctual

While I still feel that metal bikes are for me, it helps to have your firmly held paradigm of paragons questioned and the Instinct delivered on that front. The suspension design took the very pedalable Horst Link linkage and added a lively and flexy carbon layup, delivering a wonderfully surprising ride quality.

The bike has a duality; calm and centered on ascent and eerily smooth, controlled, and fast on the descent. This sensation, paired with the flexy frame and less hollow-feeling trail resonance I often experience with carbon bikes, pushed my preconceptions of how they ride.

I found myself paying less attention to the acute terrain while descending and finding flow within the expansive plane of subconsciousness. Riding familiar terrain, where you know each line, each cut, enables you to let go and simply rely on your instincts.

Perhaps the marketing of this bike is appropriately tuned, and my entanglement with the bike was opportune. Opening season rides are eye-opening. They constantly edge on fitness, both of mind and body. I used these moments of vulnerability to question my own incredulous tendencies and feel a sense of growth and perspective.

All modern bikes are going to be varying degrees of good. It’s all about observing the bike’s nuances and capabilities, contextualizing the ride experience, and waxing poetic about the review period that makes writing about bikes so fulfilling and engaging.

For an all-day pedal bike that isn’t intimidated by juggernaut climbs or tech descents, it doesn’t get much better, ATMO, than the Instinct.

Pros

• Tried and true Horst Link suspension kinematics feels supportive on climbs…
• … and calm and planted demeanor on descents
• 140/150 platform is perfect for all-mountain trail riding while still being very pedalable
• The RIDE-4 flip chip at lower shock mount offers four positions for slight geometry tweaks
• Flip chip at rear dropout allows to change chainstay length
• The lightweight carbon chassis has some nice flex thanks to the size-dependant layup design
• In-frame storage is helpful on big days when you don’t want to wear a pack

Cons

• Expensive but worth it for people who want a lightweight chassis with in-frame storage
• Bottom bracket is a bit low for sidehill, benchcut trails with shock open

See more at Rocky Mountain.

Thanks to Josh for nailing the action photos (as always!)