A Review of the Sour Bicycles Sublime Double Choc: Stahl ist Wahl – Kyle Klain | The Radavist | A group of individuals who share a love of cycling and the outdoors.

Radavist contributor and perpetual unpaid intern Kyle Klain got to bite into Sour Bicycles’ trail full-suspension bike, the Double Choc, for a few months this spring. Read on for his thoughts and John’s photos showcasing the made-in-Germany Horst link platform…

I’ll get this out of the way up front: I love steel bikes. I love German products even more. And if a frame has beautifully machined hardware or thoughtful details baked in, I’m already paying closer attention. While I want to admit to my preordained biases, a bike looking this good better ride just as well.

These days, I tend to prefer short travel bikes. Modern suspension and geometry have come so far that you can get away with less and still ride more. Also, I was a mediocre enduro racer at best– not slow, but definitely not fast. Still, trail bikes, or bikes formerly known as All Mountain, hold a soft spot in my heart. They’re the Goldilocks zone of capability and fun.

So when Sour sent over their 29er Double Choc, a steel full suspension frame welded in Saxony and dripping with CNC’d aluminum, I was all in. This bike checks a lot of boxes for me, and I was excited to see what’s what.

Double Choc Quick Hits

€3,499 including rear shock
29er wheels front/rear
136/148 mm rear travel
150 mm front travel
Made in Germany
Steel front triangle
Aluminum swingarm
Horst Link suspension design

Stahl ist Wahl

The Double Choc is Sour’s take on the modern trail bike, filtered through a pragmatic lens. That means no carbon, no trends for the sake of trends, and absolutely no unnecessary gimmicks. What you get instead is a 4130 chromoly steel frame, welded in Saxony, built around a Horst-link suspension platform, and finished with CNC’d details that feel like the results of someone who measures in microns and dreams in Bosch.

The rear travel clocks in at 136 or 148 mm, depending on your shock stroke (50 or 55 mm), and with a flip chip letting you adjust geometry basically on the fly. That includes a steeper or slacker seat tube angle, changes in bottom bracket height, and a more or less aggressive front end. It’s reminiscent of a tool wielded in the field of battle, rather than a parking lot showpiece, even though it sure is a looker.

The suspension kinematics are classic Horst-link, meaning the braking forces stay cleanly separated from the suspension action. The result is something that climbs with ridiculous traction and descends like a much longer travel bike. It’s composed, planted, and still manages to feel alive underfoot.

And then there’s the build kit I received, which clearly was not an afterthought by Sour’s SRD team and Hayes. Manitou suspension front and rear that punches way above its price. Hunt TrailWide wheels that are light, stiff, and so far have been up to the task. Hayes Dominion brakes with strong bite and plenty of power. And to top it off, an Actofive crankset that feels like a love letter to good ole CNC manufacturing.
That’s probably a good place to start.

Die Grundlage

The Double Choc frame is a study in considered design. Forged in steel and sewn together with a rear swingarm made from CNC’d aluminum, it’s clear this bike was fully nerded from front to back. The details express that Sour cares deeply about ride quality, structural integrity, and long-term serviceability.

The main triangle includes carefully placed gussets at the head tube and seat tube junctions. These reinforcements are there to manage stress and improve stiffness under load. Nothing here is ornamental. Every structural decision reflects a focus on durability and ride feel.

Geometry lands firmly in the modern trail category. A 65.5-degree head angle provides stability without sacrificing responsiveness, and while it’s not the most aggressive HTA, I can guarantee it doesn’t hamper this bike’s ability to shape shift from trail to downhill easily. The steep seat tube angle keeps the rider in an efficient climbing position, while the reach numbers support a balanced, neutral stance on technical descents.

The rear triangle is built with square-profile stays and clean, direct lines. Tire clearance is generous. The dropout design is minimal and service-friendly. Cable routing is external, with thoughtful placement that favors ease of maintenance over aesthetic trends. Us home mechanics thank you.

At the heart of the suspension is a CNC-machined aluminum rocker link with beautiful machining lines still displayed proudly. It moves smoothly on sealed bearings and feels entirely appropriate on a frame with this level of intent. Those same bearings are easily serviceable.

A flip chip at the lower shock mount allows for minor geometry adjustments, including bottom bracket height and head angle. The Double Choc runs a Horst-link layout with a relatively linear leverage rate. That predictability in the kinematic curve makes it especially appealing to riders who know how to tune their suspension. Rather than relying on a progressive frame to do the work, it puts the control in the shock itself. With the right damper and some time spent dialing compression and volume spacers, you can fine-tune the bike to suit everything from fast, flowy terrain to deeper, choppier hits. It rewards attention to setup, not guesswork.

Double Choc Die Spezifikation

The Double Choc I tested came equipped with a 150 millimeter Manitou Mattoc Pro LE fork and a 55 millimeter stroke Mara Pro piggyback shock, putting it in the full 148 millimeters of rear travel configuration. The build, spec’d by Sour in collaboration with their partners at Hayes and Manitou, is one of the few test bikes I’ve ridden where I didn’t feel the need to change a thing.

Suspension feel, touch points, drivetrain, handlebars, and brakes: it all worked right out of the box. This suspension package is the product of Hayes’ most recent design work, and it shows a ton of promise. This is not just a budget alternative to the big names, but rather this is a fully capable, highly tunable system that feels refined and deeply considered.

The Mattoc Pro LE uses a Dorado air spring with an IRT chamber, which allows independent adjustment of initial and mid-to-late stroke spring rates. This means you can fine-tune how the fork behaves in the early travel without sacrificing support deeper in the stroke. The initial suppleness is standout. It tracks small chatter and trail texture with a calm, fluid motion that immediately improves front-end grip. The HBO (Hydraulic Bottom Out) system adds a subtle but noticeable cushion in the final 30 millimeters of travel, preventing harsh impacts without needing to overinflate the main chamber.

The damper delivers well-controlled compression performance with low and high-speed adjustments. Dialing it in is intuitive, and changes are easy to feel on the trail. Once I had the fork set up, it felt supportive under load and resisted dive without ever feeling harsh or overdamped. It rides with the kind of balance that lets you stay light on the bars while still charging confidently through rough terrain.

Out back, the Mara Pro shock pairs well with the Horst-link platform. It also uses an independent high and low-speed compression circuit and includes a three-position compression lever for quick trail-side adjustment. What stands out is the shock’s ability to stay active and planted while still offering good mid-stroke support. It recovers quickly and predictably, even under repeated hits or aggressive cornering.

Because I ride flat pedals, getting the rebound and compression just right is critical. If the rebound is too fast, my feet bounce. If it is too slow, the bike feels glued down and dead. The Mara Pro offers enough rebound range to find the sweet spot. Once dialed, I noticed how well the rear end stayed calm over high-speed chunk and successive compressions. The suspension worked with me, not against me, and that allowed me to stay committed without constantly repositioning my feet.

This suspension platform gave the Double Choc a bottomless feel with precise trail feedback. It never felt vague or undefined. Instead, it rode like a well-tuned system that had already been through a season of rider input. Few stock setups feel this composed without aftermarket tweaks. Lastly, Manitou inserted their Jack dropper post, which I never gave any thought to. I think that’s the highest compliment you can give a dropper post.

Team Hayes also spec’d the bike with Dominion T4 brakes, and they were a quiet surprise. Power is absolutely on tap, with a feel that lands somewhere between Shimano’s instant bite and Magura’s more progressive stroke. Modulation is smooth and predictable, giving plenty of control without feeling vague. Most notably, they were dead silent throughout testing—no howling, no rotor rub, just consistent performance. For a set of brakes that rarely gets top billing, the T4s bring serious kraft to the table.

Rounding out the build, the Double Choc came spec’d with a ProTaper alloy bar and matching silver stem. The stem in particular deserves mention—not just for its clean clamp interface or stiffness under load, but for how well it visually integrates with the rest of the raw aluminum details on the bike. It mirrors the finish of the Actofive rocker and crank, creating a cohesive look that doesn’t feel forced. Functionally, the bar and stem combo offered a direct, confident steering feel without any unwanted harshness. Like the rest of the build, it feels like the result of thoughtful selection rather than just ticking boxes on a brand partnership.

And lastly, the highlight is the Actofive CNC crankset; it’s hard to imagine a better visual and functional match for the Double Choc. Machined in Dresden from 7075-T6 aluminum, the cranks echo the same crisp lines and raw material honesty found in the rear triangle. They’re beautifully executed without being flashy, with a finish that complements the industrial character of the frame. On trail, they’re plenty stiff under load and never once felt like a weak link. Just like the rocker and rear end, these cranks reflect the kind of small-batch German precision that’s more about performance than posturing.

Ok, enough about the parts and components. How does it ride?

Bergsteiger

With the rear shock switched into “Work” mode, the Double Choc settles into a supportive pedaling platform that somehow still maintains an impressive amount of traction. This is where the Horst-link layout and the Mara Pro shock work in tandem to keep the rear wheel engaged without sucking energy from the rider. I was running relatively heavy low-speed compression and a middle-of-the-road rebound setting, which gave me exactly the kind of planted, responsive feel I look for when climbing on flat pedals.

The steep seat tube angle and slightly upright reach combine for a position that feels natural and efficient. The front end stays down on steep pitches, and the bike tracks straight without any wandering. It is a calm, centered climber that encourages seated pedaling and rewards smooth cadence. Small note: geometry-wise, the reach is not extensive–at least for me at 6’. Not saying I was cramped, but not nearly as stretched out as some more racing-oriented long travel bikes.

Technical sections are where things start to click. With the shock tuned right, it is easy to load up the rear suspension and use it to pop up and over trail obstacles. The traction is so good that it feels almost unfair. Rear wheel placement is intuitive and precise, and the chassis stays composed even when the trail gets awkward.

This is not an XC bike. Not anywhere close, in fact. But it climbs with quiet confidence and without drama. It gets the job done efficiently, comfortably, and leaves enough in the tank for what comes next.

I did experiment with the flip chip during a few climbs. Switching it into the steeper setting gives the bike a slightly more trail-oriented feel with quicker steering and a slightly higher bottom bracket, but the change is subtle. After a ride or two, you stop thinking about it entirely, at least until you’re descending and the steeper head angle makes itself known. I suspect swapping to the shorter 50 millimeter shock stroke would have a more noticeable effect on how the bike climbs and handles overall, but in the 55 millimeter setup, the flip chip is a nice, if minor, tuning option.

Runter wie Butter

Drop the Mara Pro into “Party” mode and the Double Choc transforms. The suspension opens up, the chassis stays centered, and the entire bike becomes joyful, precise, and eager to play. It invites you to ride off the back wheel, look for side hits, and approach the trail with a little more BMX in your body language. This is where the geometry, kinematics, and suspension tune all come together.

Cornering feels remarkably intuitive. With heels down and knees out, the bike carves like big mountain skis. You can steer from your feet and lean into the terrain with confidence. It floats through high-speed turns without washing, and it loads predictably when you push into an edge. That blend of playfulness and plushness is hard to achieve, but somehow it’s baked in here.

Even under heavy braking, the Horst-link layout keeps the suspension active and supportive. There’s no harsh feedback, and no sense of the rear end locking up or standing tall. It simply holds traction and stays in the travel. On square edges, the rear wheel moves up and out of the way without drama. Off-camber sections are equally composed. The chassis digs in and holds a line with the desperation of a scared toddler clutching their mother’s hand.

Despite riding the edge of control at times, the Double Choc never feels overwhelmed. The suspension never harshes out, and I never felt it bottom with a clunk or thud. It stays predictable, supportive, and just as happy to pop around as it is to charge down the fall line. Honestly, I didn’t know zee Germans knew how to have this type of fun.

Endlich

Do I sound smitten? Absolutely. The Double Choc is that rare kind of bike: one that stands out not just because it looks different, but because it rides better than most things with far more polish and budget behind them. It’s beautifully made in a raw, industrial way, yet refined where it matters most.

The Double Choc frame comes in at €3,499, which includes the rear shock and all the beautifully machined hardware. Mine, a size large, weighed in at around 8.4 pounds without the shock. Not exactly featherweight, but you don’t buy a steel bike for KOMs on the climb. What you’re getting isn’t some delicate carbon race frame or mass-produced aluminum shell. This is a bike built with longevity in mind.

For context, that’s heavier than a carbon Yeti frame and a bit more than an aluminum Ripmo AF, but it lands in a sweet spot. It’s more refined and unique than most alloy frames, and a hell of a lot more interesting than most carbon ones. You’re paying for German-built steel, real-deal kinematics, and small-batch execution. It’s the details, however, that really leave a lasting impression.

The Double Choc is a platform, not a prescription. There’s no proprietary nonsense here. Standard shock sizes, threaded bottom bracket, external cable routing, room to move things around, and make it your own. Want to swap in a different suspension or use the flip chip? Easy. You can completely change the character of the bike to fit your needs.

This thing drips cool. It has the kind of German precision that, if memory serves, is the best kind of precision, and if you forget, just glance down at the chainstay and you’ll see “Made In Germany” stamped in bold letters.

It climbs with composure, descends with glee, and rides like it was built by people who actually care about riding. It’s not trying to be everything to everyone. It’s just a really damn good trail bike.

But most importantly, it’s fun. Overbuilt and underhyped, the Double Choc delivers the kind of ride that sticks with you. Not because it’s flashy or featherlight, but because it just works everywhere, all the time, with a grin on its face and probably some dirt on its downtube.