The great minds behind Specialized Bicycles and ROCKSHOX have collaborated in the search for the ultimate mountain bike suspension fork. After the recent launch of ROCKSHOX’s new SID collection, and needless to say hours of testing and research, both brands have arrived on the scene with a new fork, that’s exclusive to Specialized. Namely the SID SL Ultimate Brain – equipped with (as you may have guessed) Specialized’s Brain suspension technology.
Here’s what Specialized themselves had to say…
THE POSITION – SENSITIVE BRAIN FORK
A new race tune that delivers the perfect balance of efficiency and traction to ensure every watt possible gets translated into forward motion? Check. Supple, more-responsive small-bump compliance for increased grip and less energy- sapping, momentum-killing chatter? Affirmative. A stiffer, lighter chassis? That’d be a yes. The ability to seamlessly cycle between fully-open and fully-closed literally thousands of times by the time you cross the finish line? Now you’re catching on… The new Position-Sensitive Brain successfully ups the ante, and the pace, offering both entirely new features and further refinements to one of the most successful suspension platforms in World Cup history.
EFFICIENCY BREEDS EFFICIENCY
It’s not an easy task to take XC’s most efficient suspension design and make it even faster, but once you get a taste for speed, it’s even harder not to try.
A NEW WAY OF THINKING
Resulting from countless test hours in the lab and on the race course, the new Position-Sensitive Brain’s revised tune centers around a revised pedaling platform. Aligned more closely with the sag point, the platform offers racers more support when needed, while still ensuring maximum traction throughout the fork’s travel, all while priming the Brain’s Inertia Valve system for even quicker—and smoother—transitions between damping circuits. A refined Brain Fade oil bypass adjustment allows riders to easily fine-tune the transition between free stroke and platform for the most fluid, natural-feeling Brain performance yet.
Not content to stop there, the new Position-Sensitive Brain has moved into RockShox’s svelte-yet-sturdy SID SL chassis, shedding grams while increasing stiffness for more confident handling, allowing riders to take full advantage of the extra traction on tap.
Want to learn how to tune your front and rear suspension?
DELEGATE TO DOMINATE
Nobody likes a micromanager. That’s why we gave the lockout lever its own office inside the damper all the way back in 2002. Brain, the star pupil of suspension sage Mike “Mick” McAndrews, takes Specialized’s category-changing Inertia Valve technology and allows both fork and shock to near-instantly switch between open and closed damping circuits to offer the ultimate efficiency over rapidly changing trail conditions.
By leaving lockout duties to Brain’s latest Position-Sensitive Inertia Valve, riders can focus on wringing out every last watt where it counts—their legs, not their thumbs.
Now in a package that lets riders easily tailor the Brain’s decision- making exactly to their preferences, the Brain’s performance keeps to the background, lessening needless distractions and freeing up focus to concentrate on what counts—winning.
WHAT HAS CHANGED IN THE LATEST POSITION-SENSITIVE BRAIN FORKS?
A completely new tune offers racers more platform feel while maintaining small-bump compliance, offering the perfect balance of efficiency and traction. Paired with a stiffer, lighter chassis that reduces stiction, the new Position-Sensitive Brain is the fastest fork we’ve ever created.
IS THE PLATFORM POSITION ON THE NEW POSITION-SENSITIVE BRAIN FORKS ADJUSTABLE?
While set at what testing has proven to be the most ideal balance of efficiency and traction (15mm into travel), for riders who prefer to personalize the performance and feel of the fork, the platform point can be set anywhere between 0-30mm of travel by a qualified technician by removing, adjusting and re-installing the Position-Sensitive Brain damper assembly.
ARE THERE DIFFERENT POSITION-SENSITIVE BRAIN FORK MODELS? WHAT IS THE DIFFERENCE?
Comprised of three different models, the Position-Sensitive Brain lineup is differentiated by the placement of the tool-free rebound and compression adjustments. The Ultimate SL PS-TA and SL PS-TA Brain models are adjusted from the top of the fork, while the SL PS-BA Brain’s adjustment is on the bottom of the fork.
|WEIGHT TRAVEL OFFSET||RockShox SID Ultimate SL PS-TA Brain: 1505 grams|
|TYRE CLEARANCE||29 x 2.3” across all models|
|AXLE||15 x 110mm BOOST|
|STANCHION DIAMETER||32 millimeters|
|STANCHION COATING||Hard Anodised|
|CROWN CONSTRUCTION||7050 Aluminium|
|STEERER SIZE||1.5” Tapered|
|SERVICE INTERVAL||200 Hours|
Source: Specialized Bicycles
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Thanks for the review. Can you comment on the stiffness of the platform when the Brain is closed? I have a 2019 SID Brain fork (on my S-Works Epic) and the platform is too weak — when I’m out of the saddle and sprinting, I can push right through it, which results in excessive bob (which the Brain is supposed to prevent). I am wondering if Specialized “firmed up” the platform itself, in addition to reducing the platform’s location in the travel.
Thanks for your comment! My first guess is, however, that you could possibly have a faulty BRAIN system in the SID (if it really just collapses when pressuring it during sprints). Have you perhaps had your local mechanic take a look inside?
My feeling is that the new SID SL Ultimate BRAIN has been fine tuned a lot more, to be more responsive to the riding conditions. It doesn’t offer a full lockout adjustment, but rather a compliance measure of 15mm when its at its stiffest. I think the new placement of the Position-Sensitive Brain in the chassis of the fork has definitely also helped to create a more firmer adjustment. By being more responsive.
Thanks for a great article!
The article says “SL PS-TA Brain models are adjusted from the top of the fork, while the SL PS-BA Brain’s adjustment is on the bottom of the fork.”
Do you know if there are any performance differences between these two models? Is the Brain functionality equal in both?