After four months of testing, Wil gives us his longterm review of the Giant TRX 1 carbon 29er wheelset
Giant has been producing wheels for a good few years now, primarily for its own range of mountain and road bikes, but also for the aftermarket too.
For 2019, the Taiwanese manufacturer has completely revamped its line of carbon fibre hoops. There’s the lightweight XCR carbon wheelset that you’ll find spec’d on lightweight XTC hardtails and Anthem full suspension race bikes. Then there’s the burlier TRX carbon wheelset, which is spec’d on select Trance and Reign models.
According to Giant, the TRX is its strongest off-road ‘WheelSystem’ – a reference to the fact that while made up of individual components (hubs, spokes, nipples and rims), this wheel is designed to perform as a complete, single component.
The wheelset I’ve been testing is the TRX 1, which came stock on the 2019 Trance Advanced Pro 29er 1 (check out my separate review here). The TRX 1 is also available separately in the US and Australian markets, though at this point in time, not in the UK.
New ‘Impact Resistant’ Carbon Rims
The main change over previous TRX wheelsets is found in the new carbon fibre rims, which purportedly bring a 40% increase in impact strength. Knowing full well that mountain bike rims – whether they’re alloy or carbon – get absolutely punished during their finite lifespan, Giant has utilised all the tools available in its manufacturing arsenal to make these rims as resistant to harsh impacts as possible.
The rims measure a huge 37mm wide externally, and 30mm internally. They feature a hookless profile with blunt, 3.5mm thick beads. These are reinforced at the base with thicker carbon walls to better distribute impact forces when the tyre bottoms-out on the rim.
Harder to see are the internally reinforced spoke holes. Not unlike Santa Cruz’ Reserve rims, Giant has built up the wall thickness around each of the 28 spoke holes. The key difference being that the bumps are on the inside of the rim rather than on the outside.
Hubs & Spokes
In the TRX line, there are two different wheelsets; the TRX 1 (tested) and the higher-end TRX 0. These wheels use exactly the same carbon rims, but feature different spokes and hubs.
On the TRX 1 here we’ve got DT Swiss made 360 hubs, along with Sapim Lazer spokes. In comparison, the TRX 0 upgrades to DT Swiss 240 hubs and Sapim Super spokes. Weight drops by about 100g for the complete wheelset, and the price goes up to $2,035 AUD / $2,011 USD.
Giant TRX 1 29 Composite MTB Wheel Specs
- Hookless carbon fibre rims
- Internal rim width: 30mm
- External rim width: 37mm
- Depth: 25.8mm
- DT Swiss 360 hubs w/sealed cartridge bearings & 6-bolt rotor mount
- 3-pawl freehub mechanism w/24 points of engagement
- Shimano & SRAM XD freehub body options
- Boost hub spacing only
- 28x Sapim Laser straight-pull spokes per wheel w/alloy Secure Lock nipples
- Dynamic Balanced Lacing technology
- Also available in 27.5in diameter
- Claimed weight: 1750g
- Confirmed weight: 1802g (w/included tape & valves)
- 2-year warranty for original owner
- From: Giant Bicycles
- RRP: $1,399 AUD (approx £760)
Whether you get the TRX 1 wheelset aftermarket or on a stock Giant bike, they’ll come supplied with tubeless tape, valves and sealant. Giant uses its own tubeless tape, which is not only lightweight at 5g per wheel, it’s also easy and relatively cheap to replace when needed.
I had zero issues setting these wheels up tubeless. I first ran them with the stock tyres on the Trance 29er – a Maxxis Minion DHF/DHR II 2.3in combo. I also fitted a set of lighter Specialized tyres (Ground Control & Fast Trak 2.3in), as well as a 2.6in Purgatory GRID.
While some brands continue to experiment with wider rims, most seem to be settling on a 30mm internal rim width for their trail and enduro wheelsets. This works well with most 2.3-2.5in tyres, including more contemporary ‘Wide Trail’ 2.5-2.6in tyres. You could run 2.8in plus tyres if you really wanted, but things will start to get wobbly. Personally I think 2.3-2.5in is the sweet spot for these rims.
On The Trail
At a lick over 1800g, the TRX 1 wheelset is competitive in the enduro segment. Paired to the stock 2.3in wide Maxxis Minions, it isn’t the lightest or zippiest setup out there though. That’s been exacerbated by the slow-engaging rear hub, which has a lazy 15° between each click.
While riding technical ascents with chunky flat pedals, where you need to ratchet the cranks to avoid stalling out, the lazy engagement has been noticeable.
It doesn’t bother me a whole lot though – you soon get used to it and adapt your technique accordingly. Besides, high engagement freewheels are more likely to exhibit pedal kickback on a full suspension bike.
If you must have an obnoxiously loud, high-engagement freehub though, then look elsewhere.
Speaking of the freehub, I haven’t experienced any skipping or loud popping under power, though I know others who have. Heavier and more powerful riders may want to think more seriously about the TRX 0 wheelset, which features DT Swiss 240 hub internals with the proven Star Ratchet freehub mechanism.
Compared to the previous TRX 1 wheelset (the one I cracked on that Trance 1), the new carbon rims are not only wider, they’re also shallower and more blunt in profile too.
This is a trend we’ve witnessed elsewhere. While deep-section rims might look snazzy, providing plenty of real estate for brightly coloured graphics, they’re typically very stiff. Possibly too stiff.
Stiffness is of course a valuable trait to any mountain bike wheel. It helps the bike to track in the direction you want it to. But generally speaking, you want that stiffness to be in a lateral plane rather than radially. If a rim is too stiff radially – as can happen with a deep section carbon rim – then the wheel can transmit more vibration and impact forces to the rider. The result is that the wheel feels ‘harsh’ on the trail.
Of course tyres and suspension are there to help isolate you from these vibrations, but ultimately everything on your bike is a spring. And the more effective each of those springs are at absorbing impacts, the more comfortable the ride.
With that in mind, moving to a shallower and less triangular rim profile is a tactic carbon wheel manufacturers are taking to increase radial compliance. The idea is to allow the rim to compress vertically, improving comfort while also reducing deflection.
Though the theory is sound, unless a wheelset is obviously harsh or smooth, it can be a difficult trait to evaluate in isolation. So rather than just say “oh the wheels felt so vertically compliant while also being laterally stiff” (like you’ve never heard that one before…), I decided to do some back-to-back testing.
I called up the guys at Lusty Industries (who distribute Maxxis tyres in Australia), and got some Minion DHF/DHR II tyres sent out. I fitted a pair to the FSA Gradient WideR wheelset on the Merida One-Twenty test bike (29mm wide, 1720g), a pair to the Reserve 27 wheelset on the Santa Cruz Blur (27mm wide, 1748g), and a pair to the Race Face AR-27 wheelset on the Whyte S-120 (27mm wide, 2086g).
This wasn’t exactly a perfect test. I would have liked to have tried out a bunch of other wheelsets aimed at the same market as the TRX 1, but I made do with the wheels I had at the time. With the tyres setup at identical pressures, I rode a familiar test loop on the one bike while swapping wheels out each lap. I kept the loop nice and short, so I could get as best a feel for the differences as possible.
Out of the carbon wheels tested, the TRX 1 was the smoothest to ride, particularly compared to the much stiffer FSA wheels. I kind of expected this, since the FSA rims are quite a bit deeper and more triangular in their profile. Not only was there less vibration at the contact points on the bike, I could also feel less pin-balling when riding down a particularly fast and rocky gully. This helped me track more comfortably down my chosen line, with less jerkiness from the handlebar.
The TRX 1 is still a responsive wheelset though, so don’t think that the added compliance takes away from the handling. You certainly get a nice, accurate feel when pushing through turns, and compared to the alloy Race Face wheelset, the increased precision was noticeable. The Race Face wheels are still more compliant to ride though – that’s something that alloy rims do very well. But I should also point out that the AR-27 were the only rims to suffer a heavy ding (and buckle) during the test session.
In addition to the smooth ride, one thing that stood out in particular was just how quiet the TRX 1 wheels are. I noticed this on really high-speed chatter, where the TRX 1 hoops just seemed to glide over the rocks with less noise. This is likely due to the shallower rim profile, which doesn’t seem to echo vibrations and dings as audibly as taller rims.
No, they’re not as smooth or as quiet as those Bouwmeeter rims I reviewed a while back. And I’d also really like to try out the new Crank Brothers Synthesis or Zipp 3Zero Moto wheelsets to see how they compare to the Giant TRX 1.
After properly smacking these about for four months, I’ve been really impressed with the durability of the TRX 1 wheels.
Throughout testing, they’ve been solid, smooth and just generally unassuming. There has been no pinging from spokes ‘settling in’, no play in the axles or bearings, and I’ve not experienced any oddities with tubeless performance.
One mild annoyance that is a recurring theme with hubs that use tool-free end caps, is that the cassette can occasionally come off when the rear wheel is out of the bike, dragging the freehub body with it. This happened after I’d set up the rear tyre tubeless and was tapping it on the ground to slosh the sealant around the inside of the casing. I’ve had this with other DT Swiss hubs in the past, though it seems to be less of a problem these days – possibly because the main freehub seal and end caps are a little tighter.
For the first half of its test life, I had the rear wheel setup with a Vittoria Air-Liner, knowing full well I was going to be taking the Trance 29 on some pretty feral terrain. And with the Maxxis Minion DHF only having EXO reinforcement (and not the heavier DoubleDown casing), I was worried I might end up slicing a sidewall and smashing the rim at some point.
I needn’t have worried though. I pulled the insert out for the last two months of testing and kept riding with the rear tyre set up at the same pressure of 24psi. Despite connecting the rims with rock several times (I’ve heard them bottom out quite a lot!), I’m still yet to experience any fatal damage. And I can tell you that I ain’t held back.
Still, any rim can be broken. It’s worth noting here that the TRX 1 wheelset has no rider weight limit – something that’s an occasional ‘gotcha’ with other carbon wheels.
However, according to Giant’s wheel manual, crash damage and general wear ‘n’ tear isn’t covered by the two year warranty. So brands like Stan’s, Reynolds, Sixth Element, Santa Cruz, Race Face and Bontrager are still ahead there with their respective crash-replacement schemes.
Dynamic Balanced Lacing
All of the spokes have maintained tension throughout testing, which might have something to do with what Giant refers to as ‘Dynamic Balanced Lacing’.
In a nutshell, DBL is a way of addressing how spoke tensions alter between a static wheel and that same wheel being under load. Although a wheel may be nicely tensioned on the truing stand, as soon as you load it (from pedalling, braking or simply sitting on the bike), the spoke tensions change ever-so-slightly. According to Giant, it’s this change in dynamic spoke tension, and the resulting fatigue, which can lead to spoke failure down the line.
So instead of giving the spokes even tension all the way round, Giant tensions different sections of spokes slightly differently. The difference is not huge – we’re talking a variance of 1.7 (min) to 2.25 (max) on a DT Swiss Tensiometer gauge. But the idea is that when you’re actually on the bike and riding, the tensions will be more even.
It might sound like OTT marketing speak, though it’s worth noting that Shimano does a similar thing with its own wheelsets. And while it isn’t something you’re likely to feel while riding, if it helps to improve the wheels’ durability and ongoing stiffness in the longterm, then that’s surely a good thing.
As for the spokes themselves, there are three different lengths for the 29er TRX 1 wheelset (290, 294 & 298mm). As well as being able to source these through Sapim, Giant holds stock of a full range of spare spokes, nipples, hub bearings and tubeless accessories through its worldwide dealerships.
As a carbon wheelset designed for hard trail riding and enduro punishment, the Giant TRX 1 has been absolutely rock-solid. Throughout four months of testing, they’ve tracked accurately and reliably, rolling on with zero fuss. Unlike a lot of other carbon wheels currently on the market, they’re not overly harsh to ride either, with a good deal of compliance that keeps them quieter and smoother on the trail.
Engagement is slow on the rear hub, which may bother some more than others, and the warranty isn’t as aggressive as what you’ll find with some other carbon wheels on the market. Still, for those who are after some wide and strong carbon wheels for trail riding and enduro racing, the Giant TRX 1 wheelset is well worth putting on the list.
|TRX 1 29 Composite MTB WheelSystem
|$1,399 AUD / $1,182 USD
|by Wil Barrett for 4 months