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The Giant SLR 2 50 Disc WheelSystem is a hookless, tubeless compatible wheelset at a reasonably competitive price – you get a pair of tubeless Gavia Course tyres 'free' with it – that outperforms expectations. Unless you're talking about the rear hub, anyway.
Giant's SLR disc brake wheelsets come in a variety of depths, ranging from 36mm to 65mm, and they all have a hookless, tubeless carbon rim design. Within the 50mm range, there are two tiers; the SLR 1 at £1,198.98, and the SLR 2 we have here at £899.98.
The carbon rim is hookless and tubeless compatible, and is a decent 22.4mm wide internally and 30mm externally. This is not as wide as the 32mm outside diameter (OD) of the Cannondale HollowGram R45 or 35mm OD Roval Rapide CL II, but it's still enough to have an impact on your actual tyre width over most claimed widths.
Giant-branded hubs with a 30-tooth ratchet are used, with a Shimano HG freehub as standard and SRAM XDR as an option. Sapim Sprint hubs (24h front and rear) and alloy nipples complete the build. Tubeless valves and a few spare spokes are included in the box.
The rims have a recommended tyre size of 25-32mm, a maximum pressure of 125psi, and a maximum system weight limit of 129kg.
The pair weighs 1686g (790g front and 896g rear), and while that's not particularly light, it is comparable to other wheels at this price.
The Giant branding is quite subtle, which may please you if you ride another brand of frame.
The wheels were fitted with 25mm Giant Gavia Course 1 tubeless tyres, though 28mm is an option too – you can choose either pair at no extra cost when you buy the wheels.
The Gavias were easy to install, requiring only a single tyre lever, and inflated quickly without the need for frantic pumping or an air compressor. A perfect fit then, although once on they actually measured 28mm.
I also fitted other tyres to see how they compare, including Schwalbe's Pro Ones, which proved a little tighter but still possible to inflate with a track pump. My Continental GP5000 TLs though – known to be a tighter fit – completely defeated me. I gave up trying to get them on the rim after trying every trick and multiple tyre levers. I wish you the best of luck if this is your preferred tyre.
I tested at 70psi front and rear, a typical pressure for me and also what Giant's pressure guide recommends.
These wheels feel very stiff laterally, but this does not translate into vertical compliance, and they give a very firm ride, if not unbearably so. The choice of tyres is important, and the Gavia Course tyres don't have a very supple sidewall – there are many more comfortable tyres available, which would help here.
It would be impossible to prove anything without a wind tunnel, but these wheels do feel quick when maintaing speed. With such a stiff build they feel quick when accelerating, too.
The wheelset really stood out in crosswinds, being very easy to manage both in general crosswinds and when passing gates or other areas where the wind can have a significant impact. Weather conditions during testing included some very windy and gusty conditions, but I never felt unsafe or nervous at any speed.
They excelled downhill, with an extremely stable ride with no twitch and fantastic stability – in fact, I feel they are the best wheels I have ever used at high speeds, regardless of rim depth. On all types of downhills, from straight and fast to tight and twisty, they feel great.
The freehub pickup from the 30-tooth ratchet is a major disappointment, however, and in situations where there was any on/off pedalling, you could feel the free movement before it engaged. This is unlikely to be as much of an issue on the road as it is off-road, but it is an area where several competitors have an advantage.
At £899.98 these look a little expensive against some very good competition, even with the inclusion of £90's worth of tyres; the Prime Doyenne 56 Carbon Disc wheelset, for instance, is £599.99, and has just slightly wider 23mm/30mm rim widths.
Some aspects of the SLR 2's performance are exceptional, such as downhill and windy stability, but others – such as the slow freehub pick-up – quite literally lag behind competition that also beats these handily on price. Nevertheless, these wheels (and tyres) provide solid, dependable performance on the road that feels both stiff and quick.
Stable and confident wheels with wide, hookless rims – the freehub is on the slow side, though
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road.cc test report
Make and model: Giant SLR 2 50 Disc WheelSystem
Size tested: 50mm
Tell us what the wheel is for and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
Giant says: "The SLR 2 50 Disc is an accessibly priced carbon aero road wheel that delivers all-rounder speed and handling performance. The SLR 2 50 features 50mm aero rim profiles for efficiency on the flats and a dynamic ride quality on hillier roads. Hookless rims with a broad inner width offer greater support for high-volume tires along with enhanced sidewall stiffness for better grip and cornering."
Tell us some more about the technical aspects of the wheel?
* Hookless rim design saves weight and creates a broad 22.4mm inner rim width for increased actual tire contact patch, resulting in better traction and compliance.
* High tensile strength carbon fiber is placed at only the most crucial points to provide optimal stiffness and class-leading weight
* Wind-tunnel-proven 50mm Hookless Aero Rim Profile provides a maximum aerodynamic advantage
* A thick rim bead of up to 3.8mm on each side enhances rim bead stiffness, offering increased support for better cornering
Rim Material - Carbon
Rim Type - Hookless Clincher
Tubeless - Giant Tubeless System (rim tape and valve kit included)
Suggested Tire Size - 700 x 25C – 700 x 32C
Rim Height - 50mm
Rim Outer Width - 30mm
Rim Inner Width - 22.4mm
ETRTO - 622-22
Front Hub - Giant Alloy, Centerlock
Rear Hub - Giant Alloy, 3 Pawl 30 Tooth Driver, Centerlock
Hub Compatibility - Shimano HG, SRAM XDR (XDR driver sold separately)
Bearing - Sealed Cartridge
Front Axle - 100x12 Thru Axle
Rear Axle - 142x12 Thru Axle
Spokes - (Front): SAPIM Sprint, (Rear): SAPIM Sprint
Lacing - (Front): 24H, (Rear): 24H
Nipple Type - Alloy
Warranty - 2 years
Weight - (Pair): 1686g, (Front): 745g, (Rear): 941g
The rim construction is good, with a wide internal diameter and tyre installation that proves easy with Giant's tubeless rubber.
Stiffness and stability are great, but the slow-to-engage freehub is a let down.
For the price the weight is comparable to, or lighter than many other options.
Did the wheels stay true? Any issues with spoke tension?
No problems at all, they stayed perfectly true with no noise.
How easy did you find it to fit tyres?
The included Giant Gavia Course 1 tubeless tyres were simple to fit, while a set of Schwalbe Pro One tubeless were OK. I gave up on some Continental GP5000 TLs though, as they were very tight.
How did the wheel extras (eg skewers and rim tape) perform?
No problems, with tubeless valves and spare spokes included.
Tell us how the wheel performed overall when used for its designed purpose
The wheels feel fast, and the wide internal rim creates a wide actual tyre width. The extra width doesn't deliver a magic carpet ride and the freehub pickup is slow, but stability downhill and in windy conditions is a real highlight.
Tell us what you particularly liked about the wheel
The stability and confidence downhill, their useability in all weather conditions, and easy fitment when using Giant tubeless tyres.
Tell us what you particularly disliked about the wheel
The slow freehub pickup, and they're not quite as comfortable as some other carbon wheelsets.
How does the price compare to that of similar products in the market, including ones recently tested on road.cc?
While roughly in line with other big-name brands, these look a bit expensive against some high-quality competition – you can easily save £200+ on some very similar alternatives.
Did you enjoy using the wheel? Yes, especially as I love the downhills
Would you consider buying the wheel? Possibly
Would you recommend the wheel to a friend? Possibly
Use this box to explain your overall score
While some areas can't match other wheels – the 30-tooth freehub ratchet's slow pickup being one example – the general performance is still good, especially downhill, where they feel superb.
About the tester
I usually ride: My best bike is: Cannondale SystemSix
I've been riding for: Over 20 years I ride: Every day I would class myself as: Expert
I regularly do the following types of riding: road racing, cyclo cross, sportives, mtb, Lots of gravel style riding
Matt is an endurance nut who loves big rides and big events. He's a former full-time racer and 24hr event specialist, but now is also happy riding off-road on gravel bikes or XC mountain bikes and exploring the mountains and hills of Mid Wales.