Hyperlight Rims

Starting from just 955 grams for a 45mm-deep wheelset, the GCX Hyperlight truly represents the next generation of carbon wheel. They are the world's lightest UCI approved road/gravel wheels. One of the primary ways this was achieved was with a cutting edge carbon layup. Our lightweight rims are essentially unmatched when it comes to low inertia, significantly improving acceleration. They currently represent the lightest production wheels of their rim depth. Not only are they lightweight, but they are also responsive. In laboratory testing, the GCX45 Hyperlight has been shown to have a lateral stiffness 14% greater than the GCX45 Ultralight and 29% greater than the RCX45 Ultralight. 

The rims are hooked, feature 25mm inner widths, and are tubeless compatible. In order to compensate for the additional weight of the valve on tubeless and inner tube setups, we have added carbon fiber to the rim directly opposite of it in order to balance the wheel, creating a smoother ride.

GCX Hyperlight wheelsets can survive 100-joule vertical impacts, making them 2.5x stronger than the UCI standard demands, matching the strength of the GCX and RCX Ultralight wheels. This makes the wheels strong enough for everyday riding and even racing, not just climbing. Tubeless tape comes pre-installed, and tubeless valves and spare spokes are included in the box.

Decals are laser engraved, giving the wheels a unique, minimalistic aesthetic while saving additional weight. Learn more about laser engraving here.

See here for more information on the difference between Hyperlight, Ultralight, Light, and Team version wheels.

Rim Profiles

Precision Ratchet Hubs

At Particle, we try to avoid marketing trends and tech that don’t offer real world performance gains. For this reason, we have chosen to use the gold standard of hub design, the star ratchet. The RCX Hyperlight comes our SR1 hubs as standard.

The SR1 is perhaps the lightest hub ever made for the newest generation of carbon spokes. They feature aerospace-grade aluminum alloy, low-friction coating ratchets, and a choice between TPI steel and ceramic bearings.

The freehub mechanism uses 36T ratchets, which offer a balance between engagement, low rolling resistance, and longevity.

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, therefore lowering rolling resistance and improving bearing longevity. The hubs use labyrinth seals and double layer contamination barriers, so there is a significant reduction in the likelihood of ingress, effectively protecting bearings and ratchets from the elements.

Servicing is simple, as no tools are required. Star ratchets are also simple to clean and replace.

Carbon Spokes

In order to push the limits of what a performance wheelset can be, GCX Hyperlight wheels come with 4th generation replaceable carbon spokes. 4th gen spokes weigh just 2.1 grams including nipples, making them the lightest spokes commercially available. As opposed to most carbon spokes, they offer a more comfortable, compliant ride, that is more akin to steel spokes. 4th generation spokes achieve such a low weight due to titanium spoke heads and threads as well as different profile. Note that 4th generation carbon spokes are 13% more compliant than 1st, 2nd, and 3rd generation spokes, giving them a ride feel more closely resembling steel spokes.

One thing that not well-known is that not all replaceable carbon spokes are made the same. After comparing the carbon spokes from several manufacturers, we have settled on what we feel is the future. The hubs we have chosen have closed flanges, ensuring there is no risk of our spokes popping out, which is a concern on some carbon spoke wheelsets. In addition, spokes are mechanically secured so they do not twist, ensuring they always stay in the most aerodynamic orientation.

Our carbon spokes have been thoroughly tested and can survive more than 4000 newtons of tension, as opposed to steel spokes, which break under loads of between 2600-3200 newtons.

Steel and Ceramic Bearing Options

One of the most overlooked parts of a wheelset is the bearings. GCX Hyperlight wheels come with the choice between TPI steel and ceramic bearings. TPI bearings have improved seals and tighter tolerances when compared to S&S bearings, increasing their lifespan. The front hub has large 6803 bearings, improving durability, increasing longevity, and reducing rolling resistance, while each rear hub uses two 15267 bearings. The freehub features two 6802 bearings. Our bearings use mixed contact seals to protect them from contamination, improving longevity, while offering low rolling resistance.

For more information about steel vs ceramic bearings, please see this article.