Particle’s 835g RCX27 Hyperlight is the world’s lightest UCI-approved carbon road wheelset

To really achieve success, you need to focus on the details. That’s why the modern world is filled with phrases like ‘sweating the small stuff’, or ‘marginal gains’, or even why the book Atomic Habits has been such a hit.

So when it comes to a racing bike’s carbon wheels, any brand that calls itself Particle suggests an attention to detail, right down to the molecular level.

And in this case, that name isn’t an empty promise. Particle – a young, Hong Kong-based company, founded by an American but which uses the very best of Chinese manufacturing – has taken its existing knowledge of bicycle carbon wheel technology and maximised every smallest detail.

Particle’s background

The products themselves are so exciting, we don’t want to spend too much time covering Particle’s corporate history, but it’s always worth knowing the details behind a brand’s provenance.

With years of experience working for a well-known Chinese OEM and wheel brand, Particle founder Patrick Clark had accrued extensive inside knowledge of which wheel component manufacturers have the best engineers, most advanced manufacturing processes, and tightest quality control. But it was only by creating his own company – Particle – that he has finally had the opportunity to bring these individual market leaders together.

That means Particle has been able to source the finest rims, hubs, spokes and bearings, with no motivating factors other than simply finding and using the best. “There are many excellent suppliers who have their own specialties if you know where to look, and we are glad to have the freedom to work with those who we are confident in,” Patrick says.

In this piece we are going to focus on Particles awesome RCX27 Hyperlight road-specific wheels, although the brand’s GCX Hyperlight road/gravel wheels are equally impressive. Whatever your intended use, Particle’s products boast details quite unlike any other. For example, all of Particle’s carbon wheels can survive more than twice the UCI Vertical Impact Test standard. Then there is the use of things like replaceable carbon spokes, star ratchet hubs, and even offering riders a choice of bearings.

We’ll examine all those elements in greater depth in a moment. The key factor for now is that no other UCI-approved wheelset can match the 835g total weight for Particle’s RCX27 Hyperlight road bike carbon wheelset.

Note that Particle also offers the world’s lightest mid-depth UCI-approved road/gravel GCX45 and GCX52 Hyperlight wheelsets, weighing just 955g and 995g respectively with 25mm inner widths for road and gravel. They are currently being tested by Particle’s two sponsored UCI Continental pro cycling teams. These wheelsets use the same hubs, spokes, and bearings as the RCX27 Hyperlight, but hand have higher 100kg max weight limits and increased stiffness.

How does Particle do it? Let’s look at those details…

Particle RCX27 Hyperlight Road – $1,999

• 835g a pair
• Tubeless ready, hooked rims
• Fourth-generation replaceable aero carbon spokes
• Precision ratchet hubs
• Steel and ceramic bearing options
• Comes with tubeless valves, spare spokes, pre-installed rim tape, and a spoke tension and wheel trueness quality control report
• UCI approved
• Free shipping
• 3-year limited warranty with extendable 5-year and lifetime warranty on rims

Four key ingredients go into any wheel’s overall performance: rims, spokes, hubs and their associated bearings. We’ll start at the outside and work our way inwards, beginning with the rims.

Thanks to an advanced carbon lay-up, Particle’s RCX27 Hyperlight Road rims have been designed to maximise lateral stiffness, only flexing 8.3mm under a 30kg load. The rims are also almost unmatched when it comes to low inertia, significantly improving acceleration.

With 24mm inner widths and 28mm outer widths, the RCX27 Hyperlight Road rims feature ETRTO-compliant mini-hooks, offering the weight benefits of hookless wheels with the security of a hooked rim.

Then, in order to balance the wheel and compensate for the additional weight of the valve – and, ultimately, create a smoother ride – Particle has also placed additional carbon-fibre to the rim directly opposite the valve.

The rim decals are laser-engraved, giving the wheels a unique look while saving additional weight. Tubeless tape comes pre-installed, and tubeless valves and spare spokes are included in the box.

And, as we mentioned, the RCX27 Hyperlight Road wheels have survived impact tests that are more than twice the UCI’s requirements, meaning they are suitable for everyday riding, not just hill climbing.

Carbon spokes

In order to push the limits of what a performance wheelset can be, Particle’s RCX27 Hyperlight Road wheelset comes with fourth generation replaceable carbon spokes. Thanks to the use of titanium spoke heads and threads, as well as a new profile, these spokes weigh just 2.1 grams (including nipples), making them the lightest spokes commercially available.

Particle decided to use hubs with closed flanges, ensuring there is no risk of spokes popping out – a concern on some carbon spoke wheelsets. In addition, the RCX27 Hyperlight Road’s spokes are mechanically secured so they do not twist, ensuring they always stay in the most aerodynamic orientation.

Unlike most carbon spokes, they have also been designed to offer a compliant ride with enhanced comfort, more akin to the feel of steel spokes. However, unlike steel spokes, Particle’s carbon spokes have been thoroughly tested to survive more than 4000 Newtons of tension; steel spokes typically break under loads of between 2600-3200 Newtons.

Hubs and bearings

Particle says it tries to avoid marketing trends and tech fads that don’t offer real-world performance gains. For this reason, it has opted to use the proven DT Swiss-style star ratchet, with the RCX27 Hyperlight coming solely with Particle’s higher-end SR1 hubs.

Featuring aerospace-grade aluminium alloy, the SR1 hubs are supremely light. But that doesn’t come at the expense of longevity: the SR1 hub uses 36T ratchets. The ratchets’ low-friction PVD coating and choice of either TPI steel and or ceramic bearings – with tighter tolerances and better sealing – means owners can enjoy extended lifespans.

The SR1’s hub shells and axles have been machined to 0.005mm and 0.003mm tolerances respectively, making them the most precise hubs available. And the hubs’ use of labyrinth seals and double-layer contamination barriers significantly reduces the likelihood of ingress, effectively protecting bearings and ratchets from the elements.

Servicing is simple, with no tools required, and star ratchets are also simple to clean and replace.

One final detail: Particle is committed to being fully transparent and open so it is important to recognise that – despite the RCX27 Hyperlight Road wheelset’s impressive durability details – there is a 90kg system weight limit. Heavier riders can be accommodated on one of Particle’s other wheelsets, including the sub-1kg GCX45 and GCX52 Hyperlight road/gravel wheelsets, which can support rider weight limits of 100kg. Their other road and gravel wheels can support up to 140kg.

Particle RCX27 Hyperlight Road – detailed spec

General

• Wheelset weight: From 835g ±30g
• Maximum system weight: 90kg
• Tyre width compatibility: 28-45mm
• UCI Certification: Yes
• Intended use: Road cycling

Rims

• Rim type: Tubeless ready, hooked
• Rim depth: 27mm
• Internal rim width: 24mm
• External rim width: 28mm
• Finish: Paint-free matte, unidirectional

Hubs

• Freehub mechanism: Star ratchet
• Engagement: 36T
• Bearings: TPI steel or ceramic
• Brake interface: Center Lock disc
• Material: Aerospace aluminium

Spokes

• Spoke type: Fourth-generation 2.9mm aero carbon
• Spoke interface: Replaceable, mechanically secured
• Front/rear spoke count: 20/20
• Front spoke lacing: 2X/2X
• Rear spoke lacing: 2X/2X

Particle’s social conscience

Finally, while Particle makes no secret of its desire to create the absolute best bike wheels for road cyclists, that doesn’t have to come at a cost to the rest of the planet.

Particle has pledged that 10% of its profits are given to World Bicycle Relief: a non-profit that has donated over 900,000 bicycles to those in need.

And Particle is also dedicated to making its carbon wheels more environmentally sustainable. Again, it’s a matter of details, such as: minimal packaging; non-woven fabric storage bags; local sourcing; environmentally friendly manufacturing processes; and upcoming recyclable carbon thermoplastic spokes.

So Particle wheels bring less weight to your bike, and reduce the burden on the environment, too.

To find out more about the Particle RCX27 Hyperlight Road wheelset and any of Particle’s other amazing produces, visit particle-bike.com