Particle GCX45 Hyperlight Review: The Lightest Wheels I Ever Tested!

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So, I’ve already tested over 20 pairs of Chinese wheelsets. But the Particle GCX45 Hyperlight wheels have to be the most ridiculous wheels I’ve tested. Why? Because these are the lightest ones yet. They weigh just 956g at 45mm! But how do they actually ride? In this review, you’ll find out.

My GCX Hyperlight wheels scoring at a glance:
Crosswind Stability 5/5 | Stiffness 5/5 | Riding Comfort 5/5 | Speed Maintenance 4/5 | Tire On 3/5 | Trueness 5/5 | Spoke Tension 5/5 | Dishing 5/5 | Price 2/5 | OVERALL 4.3/5
More about this road wheels scoring.

Particle GCX Hyperlight: Main Features and Specs

Here are the main features and specifications of the Particle GCX Hyperlight 45D wheels. Other rim depths (45/52D and 52D) are also available. I find them a bit redundant, and I would love to see deeper options (let’s say around 60mm front and rear).

First Impressions and Unboxing

The Particle wheels arrived in a basic, brown box with a covered-up logo. I guess this was due to customs clearance. The first thing I noticed was how ridiculously lightweight the package was. It literally felt like it was empty.

I also want to highlight a small detail. Instead of using tons of plastic adhesive tape, Particle uses paper tape. They also use paper envelopes and limited plastic inside the box. These make the packaging a bit more environmentally friendly.

Anyway, the wheels were protected by two foam wheel bags and protective covers. Surprisingly, there were no end cup protectors as I’m used to from other manufacturers, so I hope this won’t cause issues with Particle shipments if they aren’t handled carefully.

The rim tape was already installed, and tubeless valves are also included. The best thing was the wheel-building report, though. This is what I would like to see in all wheelsets, as it clearly signals that the manufacturer cares about quality. By the way, below are some images from factory QC testing.

In-House Tests

These tests provide a better understanding of the wheel’s assembly quality. So, did the GCX Hyperlight pass them?

Lateral and Radial Trueness

The rear wheel’s lateral trueness was perfect. However, the front wheel had a small deviation of less than 0.3mm. It’s no big deal, it’s just not perfect.

Spoke Tension

The spoke tension was incredibly consistent on the front wheel, but the rear wheel had 4 spokes outside the 5% average. However, this is still within my tolerance for a 5/5 score, so no issues (like twisted spokes) here.

Rim Centering (Dishing)

The hubs were perfectly centered, as the dishing tool showed no gap between the end cap and the dishing tool pin. This is rare because usually, at least a sheet of paper can be pulled through. See the following photos.

A Look Inside

I also took a few photos from inside the rim. It was basically perfectly smooth, and I have not encountered any epoxy remnants. Based on the dozens of wheelsets I’ve seen from the inside, I would rate this one among the cleanest.

The Difficulty of Putting the Tire On and Off

Particle GCX Hyperlight are hooked. I always use Tufo Comtura 4 TR 28 mm tires to get consistent results when mounting and seating them. I managed to mount tires on them without tire levers. I also managed to seat them with a floor pump, though it took me two tries because I needed to adjust the tire’s fit a bit. However, I didn’t have to resort to using a compressor.

Riding Experience

I’m not gonna lie. I was extremely excited about trying these wheels. They are 250g lighter than the lightest wheels I had previously tested. Sub-100g differences are hardly noticeable, but 250g should make a difference…

Surprisingly, the first-impression difference didn’t feel as pronounced. Or maybe I’m getting too spoiled, haha. Anyway, I rode these wheels on Winspace SLC5 first. This bike is less stiff than the Winspace T1600. I mean, yeah, the setup was responsive and excellent for climbing, but I felt like it could be even better. After testing the wheels with the T1600, I found out that the low weight of these wheels, together with a stiff bike, is where the magic happens.

I previously used the MovingSports SL1200cs with the T1600, so when I replaced them with GCX, I could feel the difference, mainly in accelerations and out-of-the-saddle efforts. It’s basic physics. They simply don’t require as much force to get spinning, and getting up to speed feels easier.

However, I feel like they are not maintaining momentum as well as heavier wheels. I noticed this on most lightweight wheels. The feeling is simply different. It’s easier to get the wheels up to speed, but when I stop pedaling, it feels to me like they lose speed faster. Please, notice that I use the word “feel”. I have not conducted any unscientific testing. Lightweight wheels simply feel more lively and snappy, suiting riders who like to attack or to scenarios where you change speed often (like criteriums).

The carbon spokes are from Vonoa. These are the 4th generation, weighing just 2.1g per spoke. They are thinner, so they are a bit more compliant than the 4.5mm version used on other wheels, such as the HYPER 5. GCX45 feel marginally more comfortable than other carbon-spoked wheelsets. But again, this is a claim based on feel, and it’s not measurable. Of course, I always use the same tires and tire pressure for comparable results.

The crosswind stability is great, most likely thanks to the 5mm shallower profile than most wheels I test, the U-shaped rim profile, the 31.6mm external rim width, and narrower spokes. This makes the wheels a good choice for women or lighter riders who might struggle in strong winds.

The rear hub uses a standard 36T ratchet and enclosed flanges. The ratchet uses a newer type of spring called a ratchet wave spring that should provide a more even distribution of force. I’ve seen it on a couple of wheels, and I believe it will become more common, but so far it’s been used only on the more premium wheels.

By the way, the rear hub handled low-cadence, high-power efforts without any issues, and after about 500 km on these wheels, I haven’t had any problems with it. The freehub’s noise is ideal for me, not too loud, not too quiet. The hubs on these wheels feature steel S&S bearings, but you can upgrade to ceramic.

My 28mm Tufo Comtura 4 TR tires inflate to ~32mm on these wheels, so the tire-rim transition is quite smooth.

Other things worth mentioning are that Particle donates 10% of its revenue to charity and offers a crash-replacement discount of 25%. I also like their transparency about their QC testing and comparative testing, as well as the included wheel building report.

Overall, these are high-end wheels suitable for weight weenies and those who love the wheels’ immediate responsiveness. Remember, they have a lower weight limit of 100kg (usually, carbon wheels have a weight limit of around 120kg).

By the way, I also managed to improve some of my PRs with them. You can check out the following ride.

Particle GCX Hyperlight Alternatives

I have not tested direct lightweight alternatives to Particle GCX wheels, as these are a new generation of sub-1-kg wheelsets. You can check out the table below, which lists the wheelsets I tested and my scores in each area.

My Verdict

Sub-1-kg carbon wheels are mindblowing on paper, and ride-wise, they don’t disappoint, at least not if you are looking for high responsiveness, good riding comfort, and crosswind stability. They feel like they don’t maintain speed as well as heavier wheels do. They feel marginally more comfortable than other carbon wheels I tested, most likely thanks to thinner, more compliant carbon spokes and shallower rim depth.

The available rim depths feel a bit redundant, though, so instead of offering 45mm, 45/52, and 52mm, I would personally stick with 40mm, 50mm, and 60mm (+/-5mm). This is what most brands do, and I think for a good reason.

I recommend them for weight-weenies and climbers, or riders who like to attack or need to change speed often (like criterium racers). They are probably overkill if you live in a flat area and love steady effort. These wheels thrive in hilly and mountainous terrain. Also, remember that they have a lower weight limit, so despite their higher-than-ISO-standard product testing, I recommend looking elsewhere if you are above 90 kg.

The product for this review was kindly provided by the manufacturer. This did not influence my overall verdict or my opinion about the product. You can learn more about how I approach reviews here.