Compared to Ridley’s previous gravel racer, the Kanzo Fast, which secured victory in our big 2023 gravel race comparison test, the brand-new ASTR RS wants to be significantly more modern. Tire width, cockpit, and aerodynamics are all state-of-the-art, which is supposed to make the difference in demanding gravel races. We’ve tested the ASTR RS to see if it delivers.
The Ridley ASTR RS was developed in close collaboration with the Classified Ridley Factory Team. To meet the increased demands of modern gravel races, Ridley combined the features of their two top gravel bikes with new aerodynamic approaches and significantly reduced weight.
The ASTR RS is designed to deliver the precise, direct handling of a race bike while also setting new standards in aerodynamics, and, at the same time, is built to handle much rougher gravel tracks. As a result, the tire clearance has grown significantly to an impressive 52 mm, and the geometry has been adjusted accordingly. The Ridley Kanzo Fast, which secured the coveted Best in Test title in our big 2023 gravel race comparison test, has a strong race DNA with razor-sharp handling and optimised aerodynamics. The Ridley Kanzo Adventure, also a master of its class, won the gravel adventure comparison test. The ASTR RS inherits its generous 52 mm tire clearance, remarkable versatility, and outstanding off-road capabilities.
Ridley makes one thing clear: the ASTR RS is a thoroughbred, highly specialised race bike aiming for the podium, not an adventure bike that can race if needed. The experience of recent years has shown that in gravel races like the Unbound 200, it’s becoming increasingly important to optimise aerodynamics and rolling resistance on rough gravel tracks at an average speed of 35 km/h over a distance of 320 km. A quick glance at the bikes of this year’s top 10 clearly shows: wide tires, deep rims, and narrow cockpits.
The Ridley ASTR RS in detail
In typical Ridley fashion, the ASTR RS can be customised to your personal preferences using the manufacturer’s online configurator. Here you can customise the paint job and spec to suit your preferences and budget. Our test bike comes in one of the three standard paint finishes and relies exclusively on top-tier components.
The SRAM RED AXS XPLR 1×13 drivetrain relies on a direct-mount rear derailleur and provides a wide gear range with smaller gear jumps. This is meant to ensure precise, fast shifting while increasing the drivetrain’s durability. The expensive top-tier package is rounded off by an outstanding, powerful one-finger brake.
The frame of the ASTR RS is also compatible with 2x drivetrains and comes standard with a front derailleur mount, which can be used as a chainguide mount when running a 1x setup. The only limitation is that the maximum tire clearance is reduced from 52 mm to 47 mm when using a 2x setup.
A trend that’s already widespread in the pro road peloton is narrow cockpits, which allow for the most aerodynamic riding position possible. The new Forza NIMBUS Pro one-piece cockpit measures 36 cm wide at the hoods but becomes significantly wider in the drops thanks to a generous flare, providing plenty of control on technical descents.
Ridley ASTR RS
€ 11,699
Specifications
Fork Ridley
Seatpost Forza Carbon
Brakes SRAM RED AXS 160/160 mm
Drivetrain SRAM RED XPLR AXS 1x13
Chainring 42T
Stem Forza Nimbus Pro
Handlebar Forza Nimbus Pro
Wheelset DT Swiss GRC1400 12 x 100/12 x 142 mm Through Axle
Tires Vittoria Terreno Dry 700 x 47c
Cranks SRAM RED AXS 172.5 mm
Cassette SRAM RED XPLR 10-44T
Technical Data
Size XS S M L XL
Weight 7.82 kg
Specific Features
That aerodynamics are becoming increasingly important is also evident in the wheel choice. The deep 42 mm DT Swiss GRC 1400 SPLINE 42 wheels, with an internal width of 24 mm and a rim width of 32 mm, are definitely suitable for wide tires. However, for better aero performance, the new DT Swiss GRC 1100 Dicut 50 gravel wheelset would make more sense, as it’s better suited to wide tires. That the wheel-tire combination is crucial for aero performance has already been shown on road bikes, and as you can see: road bike trends are making their way to gravel bikes.
The fitted Vittoria Terreno Dry tires in 47 mm width look great on the bike. However, despite their fast tread pattern, they didn’t fully convince us in our gravel tire comparison test due to high rolling resistance and limited puncture protection.
Another piece of evidence supporting this theory is the fork of the ASTR RS, which, like Ridley’s all-round race bike, the Ridley Falcn RS, aims to efficiently channel airflow past the down tube using a diffuser. Ridley developed an aero bag system in collaboration with Apidura that minimises drag and fits perfectly to the ASTR RS. The system grows with the frame size and offers plenty of storage for long races with few rest stops. For easy attachment, there are mounts in the front triangle and on the top tube. Additionally, the frame can take up to three bottle cages. However, as expected on a purebred race bike, you won’t find mounts for mudguards or a luggage rack.
The geometry of the Ridley ASTR RS
When it comes to geometry, the Ridley ASTR RS takes many cues from the reigning gravel race king: the Ridley Kanzo Fast. At 71.5°, the head angle is identical, ensuring precise handling. Despite the significantly more generous tire clearance, the chainstays remain the same length, which is possible thanks to a cut-out in the seat tube. This is intended to preserve the bike’s nimble acceleration and agility.
The top tube and wheelbase have been slightly increased to provide more stability at higher speeds. The head tube shrinks by a substantial 18 mm, allowing for a much more aggressive riding position. The ASTR RS is available in five different sizes, XS to XL.
Size | XS | S | M | L | XL |
---|---|---|---|---|---|
Seat tube | 475 mm | 500 mm | 520 mm | 550 mm | 575 mm |
Top tube | 525 mm | 545 mm | 565 mm | 585 mm | 600 mm |
Head tube | 115 mm | 130 mm | 150 mm | 175 mm | 200 mm |
Head angle | 71.0° | 71.0° | 71.5° | 71.5° | 71.5° |
Seat angle | 74.5° | 74.0° | 74.0° | 74.0° | 73.5° |
Chainstay | 425 mm | 425 mm | 425 mm | 425 mm | 425 mm |
BB drop | 75 mm | 75 mm | 75 mm | 75 mm | 75 mm |
Wheelbase | 1006 mm | 1027 mm | 1043 mm | 1064 mm | 1085 mm |
Reach | 376 mm | 392 mm | 406 mm | 419 mm | 432 mm |
Stack | 536 mm | 550 mm | 571 mm | 595 mm | 619 mm |
Ridley ASTR RS first ride test
Expectations for the ASTR RS are sky-high. Can Ridley live up to their success? For this first ride review, we took the Belgian manufacturer’s brand-new gravel weapon to the Dolomites, where we put it through the wringer on fast gravel tracks, rough descents, and steep climbs. The ASTR RS exudes race vibes even when stationary. The build quality is excellent, leaving no doubt about the quality and durability of the materials. The aggressive, narrow cockpit, deep rims, and relatively slim frame despite the massive tire clearance, make one thing clear: the ASTR RS is all about speed on rough terrain.
Ready, set, go! A few powerful pedal strokes kick off the test ride. The stiff frame efficiently transfers power to the rear wheel, ensuring nimble acceleration. Straight away, you’ll notice the lower system weight compared to the Kanzo Fast, which weighs nearly 1 kg more. Despite the 47 mm (!) Vittoria Terreno Dry tires, the bike accelerates effortlessly, both on flat terrain and steep inclines. Once up to speed, the ASTR RS holds it efficiently. The narrow cockpit and shorter head tube create a sporty riding position that makes it easy to slice through the wind. The deep rims, frame, and fork round off the aero concept, making the ASTR RS feel like an incredibly efficient bike at high speeds.
To carry the speed through loose gravel corners, you need control and grip. The 47 mm Vittoria Terreno Dry tires do a great job in this regard, providing stability and composure. If you swap to 38 mm tires, the familiar, playful handling of the Kanzo Fast returns. However, on fast, rough descents, the additional stability of wider tires makes perfect sense. On technical descents, we recommend moving your hands to the much wider drops, as the 36 cm narrow top section doesn’t offer enough control.
When it comes to comfort, the voluminous tires do most of the work, while the frame remains stiff, ensuring efficient power transfer. The 3D-printed Selle Italia SLR Boost 3D Superflow saddle and the Forza Nimbus Pro cockpit are ergonomically impressive and pleasantly unobtrusive during the ride. The same goes for the SRAM RED AXS XPLR groupset, which performs reliably in all situations and allows you to brake confidently with just one finger, even on the steepest descents.
The Ridley ASTR RS can build on the performance of its predecessors and, in our opinion, places itself ahead of the Ridley Kanzo Fast in Ridley’s gravel race line-up, which is mainly due to its versatility, low system weight, and precise handling.
Who should take a closer look at the Ridley ASTR RS?
The Ridley ASTR RS is a fast, efficient, and precise gravel racer with generous reserves for rough terrain and enough tire clearance for muddy race tracks. If you’re after a fast bike for gravel, this bike won’t disappoint – whether in the mountains or on flat terrain. While the wide tires and luggage mounts suggest fast bikepacking potential, the aggressive cockpit and sporty riding position are clearly racing-focused. If you’re looking for a nimble adventure gravel rig with playful handling, the Ridley Kanzo Adventure would be the better choice.
Conclusions about the Ridley ASTR RS
With the ASTR RS, Ridley has once again perfectly captured the trends of the gravel segment. The countless mounting points, optional 2x drivetrain, and generous tire clearance make the ASTR an extremely versatile bike, and allow you to adapt it to any race. The low system weight, efficient power transfer and strong aero performance make it the ideal bike for fast gravel racing. If you love riding fast on gravel, this is the bike for you. Well done!
Tops
- Versatile
- Well-thought-out overall concept
- Lightweight
Flops
- None
More information on Ridley.com
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Words: Jan Richter Photos: Jan Richter