Description
Argon 18 Dark Matter GRX Gravel Bike 2025
The Argon 18 Dark Matter GRX Gravel Bike 2025 is more than just a gravel bike. It is engineered to take on tough terrain, both physically and mentally. Made for riders who push through when the going gets difficult, it excels where others turn back. When the road ends and the challenge begins, the Dark Matter is ready.
Tyre clearance (57 mm)
Ample tyre clearance allows for larger tyres that improve traction, comfort and versatility. Well suited to technical trails and long days on variable surfaces.
Integrated downtube storage
Built-in downtube storage provides space for ride essentials such as tools, snacks or a spare tube, helping to keep the bike organised and streamlined.
Adventure-ready geometry
Geometry designed for control and stability over unpredictable terrain. The relaxed fit offers lasting comfort on extended rides. Compatible with a front suspension fork to boost control and comfort on rougher ground.
1x drivetrain
Fitted with a 1x drivetrain for smooth, efficient shifting and minimal maintenance. Fewer moving parts enhance reliability over rough terrain. A concealed front derailleur mount is included for those who may prefer a 2x system.
Dropper post compatibility
Allows for the addition of a dropper post, offering improved control on steep or technical descents by lowering the centre of gravity.
Mounting points for bottles, racks and mudguards
Multiple mounting points provide room for water bottles, luggage or weather protection. Ideal for bikepacking and long-distance adventures.
Dynamo routing in the fork
Internal fork routing supports a dynamo setup, enabling riders to power lights and devices without cluttering the bike’s clean look.
Internal cable routing
Cables run internally for a neat appearance and easier use with handlebar bags or other front-mounted accessories.
Technical Specification
| Crankset | GRX RX610-1, 40T |
| Rear Derailleur | GRX RX822, 51T Max |
| Shifters | Shimano GRX RX610 |
| Cassette | SLX CS-M7100 10-51T |
| Chain | CN-M7100 |
| Bottom Bracket | TOKEN T47 24mm |
| Brake Calipers | RX400 |
| Rotors | SM-RT70 |
| Front/Rear Rotor Size | 160mm |
| Handlebar | FSA A-Wing Pro AGX |
| Stem | FSA SMR-II |
| Bar Tape | Ciclovation Grind Touch |
| Headset | FSA MR127 + 3D |
| Saddle | Repente Quasar S 2.0 |
| Seatpost | Argon 18 TDS-C |
| Tyres | Vittoria Terreno T50 Mixed 700x50c |
| Wheelset | DT Swiss G1800 Microspline |
Built, Checked, Tuned and Tested
All our bikes are fully built, checked, tuned and tested by our Cytech qualified mechanics and then securely packaged, ready for delivery. All you have to do is add the pedals (if included), attach the handlebars to the stem and tighten them following the included detailed instructions or by watching our video and using the provided FREE tools. Visit our Bike Assembly page to see how you assemble your new bike once you receive it.
All bikes collected from our shop, are built, tested and ready to ride. For hassle-free home delivery and bike set-up from a qualified mechanic use our Premier Delivery Service.
Please note, occasionally, manufacturers may change the specification without notice. Bicycles do not come with pedals unless otherwise specified. Bikes ordered for delivery will not arrive with the pedals installed, please refer to the owners manual and pedal installation guides provided for guidance. We do not install accessories to bikes, including mudguards. Bikes ordered for delivery that have tubeless compatible tyres and rims will arrive with inner tubes installed or with tubeless valves installed, this will be brand dependent. Sealant is available to be purchased separately.
If you require any assistance please contact our Customer Care team.
Size Guide
Argon 18 Dark Matter GRX Gravel Bike 2025 Sizing
Delivery & Returns
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Why buy your bike from Sigma Sports?
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