Particle GCX45 Hyperlight wheelset

Can a sub-1kg wheelset really handle everything you throw at it? The Particle GCX45 Hyperlight wheels are exceptionally fast, stiff and responsive, delivering outstanding performance on the road and fast gravel. However, the lightweight construction raises questions over whether it can truly be considered an all-round gravel wheelset.

First impressions

It’s no great surprise given the name, but the first thing you notice about the Particle GCX Hyperlight wheels is the weight. At just 994g on my scales, they are seriously light, and that is immediately noticeable when handling the bike.

They also look the part, with a clean, modern design that complements that lightweight construction.

The rim profile is equally up to date, with a 26mm internal width and 32mm external width on my measurements. This gives plenty of room for modern wider tyres while maintaining a relatively deep aerodynamic profile.

At 45mm, the depth feels like a sweet spot for an all-round wheelset: deep enough to offer an aerodynamic advantage without becoming unwieldy in the wind.

Build quality seems exceptional. Everything feels well finished and purposeful, with nothing giving the impression that weight has been saved at the expense of quality.

Tech specs

The GCX Hyperlights use a hooked, tubeless-ready carbon rim. They are designed to take tyres from 28mm upwards, making them equally suited to road and gravel use.

There is a 100kg system weight limit, which is worth considering when looking at them specifically for gravel.

Setting them up tubeless was reasonably straightforward, although it took a few good attempts to get the tyres seated. The tape leaves a fairly sudden lip at the edge of the rim, which made getting the tyre over it slightly more awkward than with some wheels. Once seated, however, there were no issues.

The wheels tested came with Particle’s SR1 steel-bearing hubs and fourth-generation 3.2mm aero carbon spokes. The SR1 uses a Star Ratchet freehub with 36 points of engagement, while the hub itself is made from aerospace-grade aluminium with a Centrelock disc interface. Particle also offers the SR1 with ceramic bearings, as well as the heavier and cheaper AR1 hub in steel and ceramic-bearing configurations.

The carbon spokes are one of the more interesting aspects of the build. There are 20 front and 20 rear, with a 2x lacing pattern, and they are mechanically secured and replaceable rather than permanently bonded into the wheel.

The combination of these large aero carbon spokes with the lightweight carbon rim is a big part of what gives the wheels their impressive stiffness without adding significant weight.

A nice touch is that each wheelset arrives with a personalised inspection sheet detailing the individual spoke tensions. It’s a small addition, but one that gives some reassurance about the care taken during the final build and quality control.

On paper, it’s an impressive specification, but more importantly, the individual components make sense when you ride them. The wide rim, suitably deep profile, low weight and stiff carbon spokes all contribute to a lively feel that immediately becomes apparent on the road.

Ride impressions

Put the power down and the wheels respond immediately, whether sprinting out of a corner or attacking a climb.

The low weight is particularly noticeable for the latter. They feel eager to accelerate and never give the impression of holding the bike back, while the stiffness adds to that feeling of responsiveness when riding hard.

As I said above, the 45mm depth is, for me, close to the ideal for an all-round performance wheel. While I don’t have a wind tunnel to quantify it, they certainly felt quick and once up to speed they held momentum well, producing that satisfying aero whoosh. Yet even on some of the windiest rides, I had no concerns about being pushed around.

I’ve tested them extensively on the road, including in races, as well as on gravel rides, and they have handled both surfaces exceptionally well. The combination of speed, stiffness and low weight makes them particularly enjoyable when riding hard.

Gravel

This is, first and foremost, a race-spec gravel wheelset, and that is where its strengths really come together. The low weight, high stiffness and 45mm depth are exceptionally well suited to fast gravel where maintaining speed is the priority.

Rather than being designed for loaded bikepacking or repeatedly smashing through rocky trails, these wheels feel much more at home on the kind of fast, flowing gravel you’d find at The Gralloch or the Gravel World Championships. The 100kg system weight limit and lightweight construction naturally push them towards racing rather than adventure riding, but for that purpose they make a huge amount of sense.

The problem is that the GCX name – and the G in particular – suggests something more versatile. Gravel means different things to different riders, but to me it implies a wheel that can deal with the rougher side of gravel riding as well as the fast stuff.

During my initial testing, I hit a vertical rock with a fair amount of force on a rocky descent and cracked the rim. The wheels remained true and held pressure well enough for me to ride the 20km home, which was impressive, but the damage itself was difficult to overlook.

This wasn’t a fully loaded bikepacking setup or an exceptionally heavy rider. At 64kg, with no bags and on an 8kg gravel bike, it was about as light a load as these wheels are likely to see.

Particle subsequently supplied a replacement wheel, allowing me to put more time into testing the wheels both on and off road. The firm offers a three-year warranty as standard, with the option to extend this to five years, and the wheels also come with lifetime crash replacement, which is a sign that Particle is willing to stand behind its products.

The replacement has performed exactly as expected and, importantly, it hasn’t changed my opinion of how good these wheels feel to ride.

The experience did however make me more cautious about taking them onto rougher gravel. One of the reasons riders are wary of hyperlight wheels is durability, and for me those concerns remain. The performance is exactly what you would expect from a sub-1kg wheelset, but I still have reservations about using something this light when the terrain becomes rocky and unpredictable.

For me, the GCX Hyperlights are best thought of as champagne gravel wheels. They are superb on fast, smooth gravel and, after further testing, I can say they are among the most enjoyable gravel wheels I’ve ridden. My cracked rim experience narrows the type of riding I would choose them for though.

It is also worth being clear just how good these wheels are on the road. In fact I suspect they would spend more time on tarmac than dirt if they were my own. Particle also offers the RCX as a road-focused option, and while I haven’t tested those wheels, it does raise an interesting question for a potential buyer. If most of your riding is on the road with some gravel thrown in, does a road-focused wheelset make more sense than choosing the GCX specifically for its gravel credentials?

Value

Particle isn’t a household name in cycling, and that will inevitably be a consideration when spending over £1,300 on a wheelset. It is a relatively new Hong Kong-based company, founded by an American, which positions it somewhat differently from the traditional European and American cycling brands.

That lack of brand recognition is arguably reflected in the price, but after testing the wheels I don’t think it is reflected in the quality. The build, finish and performance all feel comparable with much more established manufacturers. For me, the wheels feel like a premium product.

Starting from around £1,350 and over £1,600 in this build, the Particle GCX Hyperlights offer an awful lot of wheel for the money. There is however plenty of competition around this price, including the Scribe Gravel Carbon 40 Berd Spoke Wheelset at £1,449, the Roval Rapide CL III at £1,548, the Hunt 44/46 Aerodynamicist UD Carbon Spoke Disc Wheelset at £1,579 and the Farsports Evo5 S Series for about £1,200.

All of these wheels have received excellent reviews and offer some crossover with the Particle’s key characteristics. The Scribe combines low weight with carbon spokes, while the Hunt and Roval focus more heavily on aerodynamic performance.

The Farsports is probably the closest comparison, offering a similarly impressive specification at a lower price. However, none combines the sub-1kg weight, carbon spokes, 45mm depth and 26mm internal width in the same way as the Particle.

Where things get really interesting is when you compare to more expensive wheels. In terms of performance, I would put the GCX Hyperlights much closer to wheels such as the Roval Rapide CLX III and Zipp 454 NSW, both of which are getting on for twice the price. I feel the Particle gives very little away when it comes to stiffness, responsiveness and maintaining speed, despite costing considerably less.

There is, however, an important caveat to that. A large part of what makes these wheels so appealing is the sub-1kg weight, but the durability concerns I experienced make it harder to recommend them as all-round gravel wheels. If you are buying them specifically for fast gravel racing or road riding, where their weight and stiffness can really be exploited, I think the value is exceptional. If you want a set of wheels you can confidently take onto rough and rocky gravel without worrying about the consequences, the equation is less straightforward.

Conclusion

The Particle GCX45 Hyperlight is an outstanding set of wheels. They are exceptionally light, stiff, fast and responsive, and the 45mm profile makes them hugely enjoyable on both the road and fast gravel. The rim failure has however left me wary of the durability trade-off.

Ultimately, I suspect these wheels would spend more time on my road bike than my gravel bike. Particle’s road-focused RCX is therefore an interesting alternative on paper, although I haven’t tested it, so I can’t say whether it offers a better package. What I can say is that the GCX Hyperlights are phenomenally good wheels, provided you understand the type of riding they are best suited to.