Giant SLR 0 65mm Carbon Wheels

The Giant SLR 0 65mm Carbon wheels are superfast, handle well for their rim depth and are impressively light considering the amount of material in the rims. They're expensive at face value but are priced to undercut similar-spec wheels from the likes of Shimano, Roval and Enve.

• Pros: Fast, stable, stiff, good quality hubs and spokes, good braking with supplied pads, tubeless kit included
• Cons: Clincher tyres don't always seat easily in the tubeless rim, braking in the wet

With its 65mm rim depth, the SLR 0 65mm 'Wheelsystem' is designed, according to Giant, for when speed is all that matters. That might suggest that handling is not top of the agenda, but stability in crosswinds is good for this type of wheel.

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The aero rim is backed up by top-quality Giant-shelled DT Swiss 240 hubs and DT Aerolite bladed spokes, making it a formidable package best suited to time trialling or fast road racing over flat or rolling terrain, although at a very reasonable 1,620g they will go up all but the very steepest hills pretty quickly.

With their mean look, they're also likely to intimidate the opposition wherever they're ridden. The unusual colouring in a couple of our pics is just the way the light catches the fibres, by the way.

This is the third set of Giant carbon wheels I've tested and I've liked all of them a lot. I sometimes wonder if Giant gets left off wishlists for upgrade wheels because it's not a specialist wheel brand. But as the world's largest bicycle company it is able to harness a huge amount of design, tech, manufacturing and purchasing power, and this shows in the performance, the quality and the competitive price of its wheels. The other thing that might deter wheel buyers is the thought that Giant wheels might not match their Specialized or Trek. Well, they're easily destickered, leaving stealth-black unbranded carbon rims.

Construction

The all-carbon rim has a 19mm internal width, which marks it out as belonging to the new generation of wider-rimmed aero wheels.

A 25mm tyre sits perfectly on the SLR 0, its sidewalls more or less flush with the 23mm external rim width, and is probably the minimum width you should use with a 19mm rim.

Spoke count benefits from these being rim rather than disc-brake wheels. The front gets just 16 radial spokes (compared to 21 in the disc version) and there are 21 at the back, in Giant's Dynamic Balanced Lacing, a clever system designed to balance spoke tension under pedalling forces for a stiffer, more efficient ride, according to Giant.

The alloy hub shells are Giant branded but contain DT Swiss internals: the Ratchet System freehub of the DT 240 hub picks up crisply and freewheels with a muted purr rather than the swarm-of-angry-bees-wielding-a-buzzsaw noise of some (Hunt, I'm looking at you). A quiet freewheel is much more sociable on a group ride.

The bladed spokes are DT Aerolite, which are lighter than the Sapim CX Sprints that Giant's website lists in the spec (this is due to be corrected).

Setup

Giant includes a tubeless valve kit and rim tape in the box, but I ran the SLR 0 65s with clinchers and tubes and they worked perfectly well.

As with the previous two Giant carbon wheels I've ridden, a standard clincher tyre bead doesn't always move up easily into Giant's tubeless rim bead hook profile, meaning you can be left with a low spot that won't right itself even when the tyre is overinflated. Dribbling a little bit of soapy water – as you would use with a tubeless setup to get a very tight tyre over the rim with a tyre lever – sorts it, but in this case dribble it into the rim after you've got the tyre over the rim (so as not to make it too slippery for thumbs) before inflating.

The good news is that getting standard clinchers over Giant's tubeless rim is achievable with thumbs, unlike with some tubeless rims. I fitted Continental Grand Prix 4 Season clinchers as it was winter when I tested them (the show must go on etc) and my palms and thumbs stayed blister-free.

For setting them up tubeless, Giant puts long tubeless valves and tubeless rim tape into the box, or will fit them with its Gavia tubeless tyres for you if you specify this.

Giant also supplies brake pads specifically for use with its carbon wheels and it is essential to use these if you want to stop safely and look after your brake tracks. You also get QRs in the box.

Performance

Giant's deepest wheels are undoubtedly fast and have, as its marketing announces, been designed for when speed is all that matters. But of course speed is not quite all that matters: there are other questions that need to be asked such as how they handle in crosswinds, whether they're stiff, whether they're comfortable and practical for riding as well as racing, and whether they stop quickly enough.

One of the reasons why aero wheels have got wider over the last 10 years is because aerodynamicists have understood that even if a wheel is very fast at zero yaw, once the wind comes in at a higher angle from the side it 'stalls' as the airflow separates, and becomes more difficult to control as well as slowing down because it's not operating as an aerofoil any more. With a fatter rim and tyre, the airflow stays attached on the 'far' side of the rim at higher yaw angles so that stability (and therefore speed) are massively improved.

The SLR 0's 19mm internal rim width makes it much wider than the older aero wheels from Zipp and Hed, and it's certainly much more stable in gusting crosswinds than those, but a gust from a gateway can still blow the front wheel off its line. It's not alarming by any means, and I was perfectly comfortable riding these wheels in a tight group ride that averaged a modest 18mph, but the fact is that with deep rims the faster you go, the more stable they are. In that sense, they really are designed for when speed is all that matters.

With a tailwind or going downhill when they are going faster and yaw angle is reduced, they absolutely fly. Likewise, riding at 25mph+ in a time trial or a road race a rim of this depth comes into its own.

Until you're going up a very steep hill and your speed drops right off, an aero wheel is still faster than a light one. I didn't notice any weight penalty at all on hills – and 1,620g is still pretty light for a wheelset in any case.

Giant's Dynamic Balanced Lacing spoking pattern, which Giant claims evens up spoke tension under pedalling forces, makes the wheels very laterally stiff with no brake rub at all – and this undoubtedly helps them climb well despite the extra weight over a set of true lightweight wheels. They also arrived perfectly in true and haven't moved a millimetre during the test period.

As for the ride quality, they ran smoothly and didn't clatter and jump on rough roads like some deep-section wheels do. In terms of comfort I found them no different from the shallow-section DT R460 PowerTap rims I had been riding previously.

However, the braking of the aluminium R460 rims was far superior to that of the carbon Giants despite Giant's claims of 'superb braking performance even in the wet': with Giant's own brake pads braking in the dry was good, but the real test for carbon rims comes in the wet and the mud, and I found myself having to grab big handfuls of brake once the muck from the lanes had worked its way into the soft-feeling grey compound.

> The pros and cons of carbon wheels

The pads seemed to get very filthy too, and I found myself silently thanking the good puncture resistance of the GP 4 Seasons (or maybe just good luck!) for not making me get my hands dirty. Having said that, I've ridden carbon fibre rims and pads with worse braking performance.

Value

As already noted, Giant is able to offer well-designed, high-quality products at competitive prices because of its place at the top of the bike industry pecking order. That goes for the SLR 0 wheels. However, I couldn't help noticing that Giant's own SLR 1 wheels are considerably cheaper for exactly the same rim. The hubs (DT 350) and spokes (Sapim CX Sprint) add 110g in weight but the SLR 1s cost £999.98. That looks like a good way to save £500 and keep the lion's share of the performance.

The Swiss Side Hadron Ultimate 485s we reviewed recently were more expensive at £1,950, but lighter with a slightly shallower rim depth.

The Giant SLR 0s, however, are cheaper than the (also slightly shallower and lighter) Miche Supertype 440 White Labels. 

Competitor wheels of similar depth that we haven't tested at road.cc include Roval CLX 64 (£2,000), Enve SES 5.6 (£2,600), DT Swiss ARC 1400 DICUT 62mm (£1,674.98), and Mavic Comete Pro Carbon SL UST (£1,800).

> Buyer's Guide: 45 of the best road bike wheels

Hunt's 50 Carbon Wide Aero wheelset at £849 is a popular choice and one often seen on the UK racing scene. Wiggle/Chain Reaction's own-brand Prime Black Edition 50 wheels are also well priced at £1,099.

Meanwhile, the Ican Aero 50 at £500 is one of the cheapest out there – but didn't review well with us for stiffness, crosswind stability and braking.

So for value, the Giants are pretty good considering they use high-end DT hubs and spokes and a proprietary (as opposed to open mould) rim, and bearing in mind their top-notch build and performance. There are cheaper wheelsets, but shortcuts in terms of materials and quality might have been taken to get to that price point.

Verdict

Superfast, high-end, competitively priced wheels that are perfect for racing or time trialling