Test of the new Canyon Aeroad CF SLX 8

The all-new 2025 Canyon Aeroad CF SLX is a subtle evolution of the previous generation of a model that has long been a benchmark for performance and versatility. Stiffer, sharper, but also more stable, this version with a Shimano Ultegra Di2 groupset and DT Swiss Arc 1400 wheels offers one of the best value for money on the market for speed and competition enthusiasts. Here is the test byone of the most successful bikes of the moment.

By Guillaume Judas – Photos: ©Vincent Lyky

The 8.0 Canyon Aeroad CF SLX 2025 belongs to the fourth generation of the Aeroad range. The frame is in the second level of the German brand's range, just behind the Aeroad CFR. It differs only in the manufacturing process, which is a little less sophisticated than on the CFR, which gives it a few dozen grams more.

As with most frames on the market, the Aeroad CF SLX is made from carbon fibers selected to meet the specific requirements of each part of the bike.. Canyon uses a combination of high modulus and intermediate modulus fibers. They are arranged in a precise orientation to maximize the mechanical properties of the frame.

High modulus fibers are used in areas requiring maximum stiffness, such as the bottom bracket and down tube, to ensure optimum power transmission. Mid-modulus fibres are placed in areas such as the seat tube and seat stays. They provide flexibility to absorb vibrations, improving comfort without compromising performance.

The manufacturing process is based on finite element analysis (FEA) and tests rigorous laboratory. This approach allows Canyon to reduce frame weight while reinforcing critical areas. This ensures durability and reliability, in addition to the dynamic behavior desired by the designers.

With a claimed frame weight of around 1kg (depending on size), the Aeroad CF SLX ranks among the lightest aero bikes in its class.. A contained weight thanks to a careful reduction in the quantity of resin used in the manufacturing process, while maintaining optimal rigidity.

Further improved aerodynamics

The fourth generation Canyon Aeroad CF SLX is based on extensive wind tunnel work and close collaboration with aerodynamics experts including Swiss SideThe brand claims a significant improvement in aerodynamics compared to the previous generation, with a saving of 7,5 watts at high speed. This performance is achieved through optimized tube profiles, complete cable integration and an overall design that reduces drag to a minimum.

On this new model, the seat tube and post and the seat stays have been slightly refined. On the other hand, the horizontal tube is a little wider. Between the head tube and the down tube, a slight offset is a little more marked than on the model we had testé in 2023. From the side, the bike is therefore a little surprising, especially in size XS, with a clearance between the front wheel and the down tube much greater than on some competing bikes.

All cables are of course concealed inside the frame and cockpit, reducing drag and providing a clean aesthetic.. Finally, the DT Swiss Arc 1400 wheels with a 50 mm high profile are an integral part of the project. They are also designed in collaboration with aerodynamic specialists Swiss Side. They seem to be perfectly suited to the bike, especially in terms of stability in crosswinds.

Their internal width is 20 mm., when many brands today go up to 22, 23, or even 25 mm for a rounder profile, supposed to offer more balance at high speed. However, by offering the Aeroad with differentiated tire sections (25 mm at the front and 28 mm at the rear), Canyon has studied its business in the smallest details.

Almost tailor-made cockpit

The Aerocockpit CP0048 adjustable cockpit is another major innovation. It allows you to easily adjust the height (up to 20 mm) and width (up to 40 mm) of the handlebar without requiring complex modifications. Such as replacing components or cutting the steering tube. A modularity particularly appreciated by those who wish to customize their position to maximize their comfort and efficiency.

The pilot's posttagIt consists of three parts. First a main T-shaped segment connected to the fork steerer by a threaded piece to replace the expander. The length can be changed compared to the model defined by the size of the bike, for about €200. The montagIt is more complex here than a simple change of stem on a more classic bike.

Note that the headset adjustment is now simplified compared to the system previously used on the Aeroad.

Then There are two extensions on both sides of the T, held by two screws. This system allows you to adjust the width of the handlebar as desired (with 390, 410 or 430 mm width). But also to facilitate the transport of the bike in certain conditions by dismantling and folding the two parts towards the frame.

A solution already present on the previous Aeroad or theUltimate, which here comes with another option, since Canyon now offers extensions with a 19° flare, for a much narrower upper part than the lower part.

It's something I don't have testThis should appeal to riders looking for a very aerodynamic position with their hands on the brake levers.

Without a doubt, Canyon is the leader with this feature, especially since changing the extensions does not require removing the brake lines.. On the cockpit that comes standard with the Aeroad CF SLX 8, I find the lower part of the handlebars a little too high and with an angle that does not favor the wedging of the hands. The flared extensions seem less high and less deep.

The fact remains that the system itself of this pilot's positiontage still shows a slight mismatch in stiffness between the upper and lower parts of the handlebar.

High level equipment

The Canyon Aeroad CF SLX 8 is equipped with a Shimano Ultegra Di2 12-speed groupset, matched with a 4iiii power meter (only in the left crank). Apart from a slight excess weight compared to the Dura-Ace group (around 250 g), there is absolutely nothing to criticize about the Ultegra Di2, as precise, fast and efficient as the top of the range Shimano.

The only criticism that can be made concerns the chainrings delivered with the bike: 52 and 36 teeth. This is the maximum offered with Ultegra. At a time when more and more competitors are adopting larger developments, it is a shame that we cannot choose larger chainrings, whether for racing on route or to participate in triathlons.

The option is not available in Ultegra, and in any case not possible at Canyon. The same goes for the crank length, imposed here by the brand. This is one of the limits of online sales, but which still allows you to optimize the price of the brand's bikes as much as possible.

Because, for a price of 6549 €, Canyon takes care of its customers. In addition to the very well-made frame and groupset, there are DT Swiss Arc 1400 wheels, Continental GP 5000 S TR tires (mounted here with inner tubes) and a Selle Italia SLR Boost Superflow Kit Carbonio saddle.

The total weight of the bike is 7,49 kg, without pedals but with bottle cages.. A beautiful machine ready to race.

Powerful yet versatile 

While the Aeroad CF SLX 8 is designed primarily for performance, Canyon has not neglected comfort, a crucial aspect for long rides and demanding races.. The seatpost provides some flexibility to absorb vibrations, while remaining aerodynamic. It also has two threaded holes for accessories such as lights and frame plate mounts.

Urban artist The bike is compatible with tires up to 32 mm, which improves comfort on the routes less smooth without compromising speed. On the route, the new-generation Aeroad isn't really a bike designed for admiring the scenery, but it remains relatively comfortable on four- to five-hour rides at a good pace.

In terms of pure performance, the machine largely delivers on its promises.. From the first pedal strokes, I could feel the overall rigidity of the bike, but a rigidity that should not be confused with too much stiffness. The Aeroad is lively and perfectly maintained over its entire length. The wheels never seem to float in the middle of the chassis, even during energetic relaunches with gears.

And yet, I did not find him uncompromising either, in the sense that it does not necessarily impose an ideal pedaling cadence or power window to get going again or maintain a good speed at the train. I was able to climb some hills quite forcefully, around 60 rpm, without feeling completely stuck as is sometimes the case with really very stiff frames.

On the flat and in the wind, the Aeroad CF SLX 8 is really efficient. Not only is it fast as shown by the cross-data from the power meter and the computer, but it also shows astonishing stability in a strong crosswind. Given the size of the tubes and rims, you of course often have to lean the bike a little to counteract the effect of the wind.

The bike shows amazing stability in a strong crosswind.

However, The steering is not very sensitive to gusts and I never felt surprised by a loss of control of the trajectory on rolling sections. It is only when going downhill at very high speed, and always in strong wind conditions, that the bike is a little more delicate to hold. This is still a characteristic often common to bikes equipped with high rims.

A bike designed for competition, but accessible to all

The Aeroad CF SLX 8 is a racing bike, with the CFR version used by professional teams such as Alpecin-Deceuninck and Movistar. However, It remains accessible to passionate amateurs thanks to its competitive price and a more versatile behavior than it seems.. This fourth generation brings from my point of view much more than a simple update. It is a real evolution that pushes the limits of what a bike can route aerodynamics can offer.

I wouldn't recommend it to those who only ride once a week, of course. It's not as advanced as some very high-end bikes that cost twice as much, and which it loses by half a kilo and a few minor functionalities.

More for anyone who is properly trained and looking for a modern, responsive, and who dream of speed and performance, it is not far from being an ideal choice., especially if we take into account its sale price, which is also extremely competitive compared to the competition.

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