Argon 18 SUM Ultegra Di2 Road Bike
The Argon 18 SUM Ultegra Di2 Road Bike delivers unmatched performance on climbs and sprints, challenging you to decide just how much mercy to show your rivals.
Designed with a rider-focused approach, the frame achieves the perfect balance of responsiveness and stability, providing a ride quality that outshines most aero frames. The Sum’s precision-engineered layup maximises aerodynamics while reducing weight. Its advanced aero-profile tube shapes eliminate unnecessary material, ensuring optimal power transfer for peak efficiency.
3D System
Argon 18's 3D Technology delivers a tailored fit without compromising safety, steerer stiffness, or aesthetics.
Road Race Geometry
Specifically engineered for razor-sharp reflexes and precision handling, this geometry caters to racers at every level.
Topological Compliance System
Through a proprietary design process, this system enhances vertical compliance and minimises road vibrations while maintaining maximum stiffness. Each TCS-equipped bike undergoes comprehensive analysis to optimise frame topology and carbon layup.
Argon Fit System
Argon 18’s size-specific geometries ensure every rider enjoys optimal performance and positioning, leaving no cyclist behind.
Elite Level Layup
Built with the same meticulous attention to detail as Pro-level models, Argon 18’s Elite-level bikes offer superior performance for the most discerning riders.
Technical Specification
| Frame | SUM |
| Fork | SUM specific |
| Headset | FSA Headset NO.55R 1.5'' + 3D |
| Integrated Cables | Yes |
| Wheels | Scope R4 |
| Tyres | Vittoria Corsa N.EXT TLR 28mm |
| Tyre Clearance | 30C (32mm) |
| Bottom Bracket | BB Ultegra SM-BB72 |
| Front Derailleur | Shimano Ultegra Di2 R8150 |
| Rear Derailleur | Shimano Ultegra Di2 R8150 |
| Crankset | Shimano Ultegra R8100 52/36 |
| Chain | Shimano Ultegra CN-M8100 12S |
| Cassette | Shimano Ultegra CS-R8100 11-30 |
| Brakes | Shimano Ultegra Di2 R8170 |
| Rotors | Shimano Ultegra RT-CL800 / F |
| Shifters | Shimano Ultegra Di2 R8170 |
| Handlebar | FSA Energy SCR Compact |
| Stem | FSA SMR-II |
| Bar Tape | Ciclovation LEATHER TOUCH Tornado Gloss |
| Saddle | Repente Quasar |
| Seatpost | SUM specific |
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.
Argon 18 SUM Ultegra Di2 Road Bike Sizing
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