Argon 18Nitrogen Pro
Argon 18's aero race bike, relaunched in September 2025 after three years of development and its fastest road bike to date by the brand's account. It was designed as a system with ATTEN x Scope Artech 6.A+ wheels made for 30 mm tyres, the one-piece ATTEN CHB-01 cockpit and aero bottle cages. The Pro is the higher of two carbon layups (the cheaper Nitrogen shares the platform), and all three Pro builds come with the same wheels and cockpit.
- From
- €13,995$14,499£13,000
- Builds
- 3
- Sizes
- 6
- Frame weight
- —
Design sketch, generated from the manufacturer's photo
Our verdict
Overall
out of 100, average of 7 categories
For racers who want a full aero system: wheels, one-piece cockpit and bottle cages developed with the frame, with published wind-tunnel gains and a 6.95 kg claimed weight. You give up colour choice and cockpit widths beyond 360 or 380 mm, and only the Red build has a power meter in every market.
Scored Oct 2026
- + Light
- + Aero-first design
- + Top-tier build kit
- − Expensive
AI-drafted from the specs on this page and reviewed before publishing. Scores are relative to every bike in the catalog when they were given, so they drop as newer bikes and parts raise the bar.
- Aero
- 92/100
- Frame
- 86/100
- Components
- 90/100
- Fit
- 80/100
- Practicality
- 72/100
- Price
- 47/100
- Weight
- 97/100
Aero claims and front-end integration
Carbon grade, weight and warranty
Groupset, wheels and power meter
Sizes and adjustment range
Travel, standard parts, servicing
From the cheapest complete-bike MSRP
From the lightest claimed weight (6.95 kg, size M)
Bike duel
Frame & platform
Frame & fork
- Frame material
- Carbon (Nitrogen Pro layup)
- Fork material
- Carbon
- Weight measured on
- Argon 18 quotes a frame under 950 g and a fork under 415 g (size M, painted)
- Frame sizes
- XXS, XS, S, M, L, XL
- Colours
- Aurora Charcoal
- Also available as
- Nitrogen, a lower-grade carbon version of the same platform
- UCI frame approval
- Approved 27 May 2025 as 'NITROGEN PRO' (frame and fork), sizes XXS-XL (6), code AR18-004 (UCI list version 2026.10.02)
Compatibility & standards
- Brake type
- Hydraulic disc
- Max rotor size
- 160 mm
- Max tire width
- 32 mm
- Bottom bracket standard
- T47 threaded, 85.5 mm shell
- Front axle
- 12 mm thru-axle (M12 x 1.5, 119 mm)
- Rear axle
- 12x142 mm thru-axle (M12 x 1.0, 167.5 mm)
- Drivetrain compatibility
- Electronic groupsets (the assembly guide covers wireless and wired routing only). 2x with 50-57T round chainrings (or oval of equivalent size); 1x up to 56T
- 1x compatible
- Yes
- Max chainring
- 57T
- Front derailleur mount
- Removable front derailleur hanger; plugs fill the holes for 1x
- Cable routing
- Fully internal
- Electronic battery location
- On the bottom bracket cover / battery holder
Bottles & storage
- Bottle mounts
- 2
- Bottle mount locations
- Down tube and seat tube, with the included ATTEN aero cages
Fit & adjustability
- Cockpit
- One-piece carbon bar and stem (ATTEN CHB-01 Aero)
- Standard stem and bar possible
- Yes
- Seatpost type
- Argon 18 Nitrogen Pro aero carbon seatpost, -20 mm setback or 'zero setback' (+10 mm forward)
- Fit notes
- 6 sizes. The CHB-01 comes in 360 and 380 mm widths with 80-130 mm stems (12 sizes). Up to 40 mm of two-piece aero spacers fit under the bar and can be added or removed without cutting brake hoses. A regular stem can be fitted (the assembly guide covers it), and IST3 headset caps are offered for Deda Alanera RS, FSA ACR/SMR and FSA SRS cockpits.
Aerodynamics
- Manufacturer aero claims
- Argon 18 says the Nitrogen is 24 W faster than its Sum Pro (reported by TOUR; tested with a rider). The white paper claims the CHB-01 cockpit saves 6.7 W against a standard bar and stem and 4.3 W against a Vision Metron 5D at 45 km/h (wind-averaged), the aero cages 1.1 W with bottles and 1.8 W empty, and that adding two bottles costs 0-3 W against 4-9 W on a traditional aero frame. The aero spacers cost 0.7 W per 30 mm of stack (Sum Pro: 1.4 W).
- Testing method
- CFD on more than 130 tube profiles and 25 fork prototypes, three wind-tunnel sessions, final tests with a pedalling rider and with mannequin legs at 45 km/h against the Sum Pro and an unnamed WorldTour aero bike. Wheels and frame were developed together with Scope.
- Tube profile
- Truncated NACA-based profiles; off-axis head tube with the steerer set back from the leading edge; wide-stance fork; dropped seat stays
Travel, maintenance & warranty
- Headset bearings
- IST3 (CeramicSpeed SLT bearings on the complete bikes)
- Derailleur hanger
- UDH (SRAM Universal Derailleur Hanger), standard or direct-mount version
- Proprietary parts
- ATTEN CHB-01 cockpit and aero spacers, Nitrogen seatpost and clamp (not shared with the Sum), ATTEN aero cages, BB cover/battery holder, thru-axles
- Sold via
- Through Argon 18 dealers
Photos
Design sketches
Builds & components
Highlighted rows differ between builds. Green marks the best value.
Nitrogen Pro SRAM Red AXS | Nitrogen Pro Shimano Dura-Ace Di2 | Nitrogen Pro Shimano Ultegra Di2 | |
|---|---|---|---|
| Overview | |||
| Price (MSRP) | €13,995$14,499£13,000 | €13,495$13,999£12,500 | €10,995$10,499£9,500 |
| Weight | 6.95 kg15.3 lb | — | — |
| Weight measured on size | M | — | — |
| Type | Complete bike | Complete bike | Complete bike |
| Notes | Colour Aurora Charcoal. Argon 18's white paper gives 6.95 kg for this build in size M (painted, with Vittoria Corsa Pro tyres and TPU tubes). | Colour Aurora Charcoal. The UK version lists a Dura-Ace FC-R9200-P power-meter crankset (52/36) instead of the standard R9200 crank; the US page doesn't list a power meter. The European and UK pages list a CeramicSpeed T47 Coated bottom bracket. | Colour Aurora Charcoal. The European and UK pages list a CeramicSpeed T47 Coated bottom bracket. |
| Drivetrain | |||
| Groupset | SRAM Red AXS E1 | Shimano Dura-Ace Di2 R9200 | Shimano Ultegra Di2 R8100 |
| Launched | 2024 · current generation | 2021 · current generation | 2021 · current generation |
| Speeds | 12-speed | 12-speed | 12-speed |
| Electronic | Yes | Yes | Yes |
| Wireless | Yes | — | — |
| Drivetrain | 2x | 2x | 2x |
| Shifters | SRAM Red AXS E1 | Shimano Dura-Ace Di2 ST-R9270 | Shimano Ultegra Di2 ST-R8170 |
| Notes | Combined shift and hydraulic brake levers | Combined shift and hydraulic brake levers | Combined shift and hydraulic brake levers |
| Crankset | SRAM Red AXS E1 Power Meter | Shimano Dura-Ace R9200 | Shimano Ultegra R8100 |
| Chainrings | 48/35 | 52/36 | 52/36 |
| Crank lengths available | 165 mm (XXS-XS), 170 mm (S-M), 172.5 mm (L-XL) | 165 mm (XXS-XS), 170 mm (S-M), 172.5 mm (L-XL) | 165 mm (XXS-XS), 170 mm (S-M), 172.5 mm (L-XL) |
| Power meter | SRAM Red AXS E1 Power Meter | — | — |
| Launched | 2024 · current generation | — | — |
| Type | Integrated in crankset | — | — |
| Bottom bracket | CeramicSpeed T47 DUB Coated | CeramicSpeed T47 BB Alpha | CeramicSpeed T47 BB Alpha |
| Standard | T47 threaded | T47 threaded | T47 threaded |
| Front derailleur | SRAM Red AXS E1 | Shimano Dura-Ace Di2 R9250 | Shimano Ultegra Di2 R8150 |
| Rear derailleur | SRAM Red AXS E1 | Shimano Dura-Ace Di2 R9250 | Shimano Ultegra Di2 R8150 |
| Cassette | SRAM Red XG-1290 E1 | Shimano Dura-Ace R9200 | Shimano Ultegra R8100 |
| Range | 10-33 | 11-30 | 11-30 |
| Speeds | 12-speed | 12-speed | 12-speed |
| Chain | SRAM Red | Shimano CN-M9100 | Shimano CN-M8100 |
| Brakes | |||
| Rotors | SRAM Paceline X | Shimano Dura-Ace RT-CL900 | Shimano RT-CL800 |
| Front rotor | 160 mm | 160 mm | 160 mm |
| Rear rotor | 140 mm | 140 mm | 140 mm |
| Mount | Center Lock | Center Lock | Center Lock |
| Wheels & tires | |||
| Wheelset | ATTEN x Scope Artech 6.A+ | ATTEN x Scope Artech 6.A+ | ATTEN x Scope Artech 6.A+ |
| Material | Carbon | Carbon | Carbon |
| Recommended tire widths | Optimised for 30 mm tyres | Optimised for 30 mm tyres | Optimised for 30 mm tyres |
| Notes | Co-developed with Scope for the Nitrogen Pro, with a rim shape re-optimised from Scope's Artech 6.A | Co-developed with Scope for the Nitrogen Pro, with a rim shape re-optimised from Scope's Artech 6.A | Co-developed with Scope for the Nitrogen Pro, with a rim shape re-optimised from Scope's Artech 6.A |
| Tires | Vittoria Corsa Pro TLR | Vittoria Corsa Pro TLR | Vittoria Corsa Pro TLR |
| Tire width | 30 mm | 30 mm | 30 mm |
| Cockpit | |||
| Handlebar | ATTEN CHB-01 Aero | ATTEN CHB-01 Aero | ATTEN CHB-01 Aero |
| Type | One-piece carbon bar and stem | One-piece carbon bar and stem | One-piece carbon bar and stem |
| Integrated stem | Yes | Yes | Yes |
| Widths available | 360 or 380 mm, each with 80-130 mm stems (12 sizes) | 360 or 380 mm, each with 80-130 mm stems (12 sizes) | 360 or 380 mm, each with 80-130 mm stems (12 sizes) |
| Material | Carbon | Carbon | Carbon |
| Weight | 320 g11.3 oz | 320 g11.3 oz | 320 g11.3 oz |
| Notes | Stock size by frame: 360 x 80 (XXS), 360 x 90 (XS-S), 380 x 100 (M), 380 x 110 (L), 380 x 120 (XL). Integrated computer mount with Garmin and Wahoo inserts and 3-12° tilt shims. Weight for 380 x 100 mm. | Stock size by frame: 360 x 80 (XXS), 360 x 90 (XS-S), 380 x 100 (M), 380 x 110 (L), 380 x 120 (XL). Integrated computer mount with Garmin and Wahoo inserts and 3-12° tilt shims. Weight for 380 x 100 mm. | Stock size by frame: 360 x 80 (XXS), 360 x 90 (XS-S), 380 x 100 (M), 380 x 110 (L), 380 x 120 (XL). Integrated computer mount with Garmin and Wahoo inserts and 3-12° tilt shims. Weight for 380 x 100 mm. |
| Headset | CeramicSpeed SLT (IST3) | CeramicSpeed SLT (IST3) | CeramicSpeed SLT (IST3) |
| Saddle & seatpost | |||
| Saddle | Repente Quasar CR 2.0 | Repente Quasar CR 2.0 | Repente Quasar CR 2.0 |
| Seatpost | Argon 18 Nitrogen Pro | Argon 18 Nitrogen Pro | Argon 18 Nitrogen Pro |
| Offset / setback | -20 mm setback (a 'zero setback' version, 10 mm further forward, is available) | -20 mm setback (a 'zero setback' version, 10 mm further forward, is available) | -20 mm setback (a 'zero setback' version, 10 mm further forward, is available) |
| Material | Carbon | Carbon | Carbon |
| Weight | 160 g5.6 oz | 160 g5.6 oz | 160 g5.6 oz |
| Notes | Weight includes clamp | Weight includes clamp | Weight includes clamp |
| Bar tape | Ciclovation Leather Touch Tornado Gloss | Ciclovation Leather Touch Tornado Gloss | Ciclovation Leather Touch Tornado Gloss |
| Included extras | |||
| Bottle cages | ATTEN Aero cages (down tube and seat tube) | ATTEN Aero cages (down tube and seat tube) | ATTEN Aero cages (down tube and seat tube) |
Nitrogen Pro price & value
Where it's cheapest
MSRPs converted at ECB reference rates of 2026-10-05 (1 EUR = 1.1204 USD = 0.8472 GBP). US prices exclude sales tax, so add your state's rate before comparing.
| Build | Market | MSRP | In EUR | vs cheapest |
|---|---|---|---|---|
| Nitrogen Pro SRAM Red AXS | USA (USD, excl. sales tax) | $14,499 | €12,941 | cheapest |
| Europe (EUR, incl. VAT) | €13,995 | €13,995 | +8% | |
| UK (GBP, incl. VAT) | £13,000 | €15,345 | +19% | |
| Nitrogen Pro Shimano Dura-Ace Di2 | USA (USD, excl. sales tax) | $13,999 | €12,495 | cheapest |
| Europe (EUR, incl. VAT) | €13,495 | €13,495 | +8% | |
| UK (GBP, incl. VAT) | £12,500 | €14,754 | +18% | |
| Nitrogen Pro Shimano Ultegra Di2 | USA (USD, excl. sales tax) | $10,499 | €9,371 | cheapest |
| Europe (EUR, incl. VAT) | €10,995 | €10,995 | +17% | |
| UK (GBP, incl. VAT) | £9,500 | €11,213 | +20% |
Ownership checklist
3 of 3 known checks pass, 1 not published by Argon 18. Why these checks
- ✓
Threaded bottom bracket
T47 threaded, 85.5 mm shell
- ✓
UDH derailleur hanger
UDH (SRAM Universal Derailleur Hanger), standard or direct-mount version
- ✓
Standard 12×142 mm rear axle
12x142 mm thru-axle (M12 x 1.0, 167.5 mm)
- ?
Works with mechanical shifting
Nitrogen Pro geometry
| XXS | XS | S | M | L | XL | |
|---|---|---|---|---|---|---|
| Stack | 486 mm19.1″ | 508 mm20″ | 531 mm20.9″ | 555 mm21.9″ | 580 mm22.8″ | 607 mm23.9″ |
| Reach | 370 mm14.6″ | 377 mm14.8″ | 384 mm15.1″ | 392 mm15.4″ | 400 mm15.7″ | 409 mm16.1″ |
| Seat tube angle | 75° | 74.5° | 74° | 73.5° | 73° | 72.5° |
| Head tube angle | 71.2° | 72.1° | 72.7° | 72.7° | 72.7° | 73° |
| Head tube length | 81 mm3.2″ | 97 mm3.8″ | 113 mm4.4″ | 138 mm5.4″ | 165 mm6.5″ | 192 mm7.6″ |
| Effective top tube | 502 mm19.8″ | 519 mm20.4″ | 537 mm21.1″ | 557 mm21.9″ | 578 mm22.8″ | 601 mm23.7″ |
| Seat tube length | 395 mm15.6″ | 425 mm16.7″ | 460 mm18.1″ | 505 mm19.9″ | 550 mm21.7″ | 595 mm23.4″ |
| Chainstay | 410 mm16.1″ | 410 mm16.1″ | 410 mm16.1″ | 410 mm16.1″ | 410 mm16.1″ | 410 mm16.1″ |
| Wheelbase | 967 mm38.1″ | 972 mm38.3″ | 975 mm38.4″ | 990 mm39″ | 1,006 mm39.6″ | 1,020 mm40.2″ |
| BB drop | 71 mm2.8″ | 75 mm3″ | 79 mm3.1″ | 79 mm3.1″ | 79 mm3.1″ | 79 mm3.1″ |
| Fork length | 376 mm14.8″ | 376 mm14.8″ | 376 mm14.8″ | 376 mm14.8″ | 376 mm14.8″ | 376 mm14.8″ |
| Fork offset | 49 mm1.9″ | 49 mm1.9″ | 45 mm1.8″ | 45 mm1.8″ | 45 mm1.8″ | 45 mm1.8″ |
| Standover | 682 mm26.9″ | 706 mm27.8″ | 734 mm28.9″ | 772 mm30.4″ | 810 mm31.9″ | 848 mm33.4″ |
| Saddle height min | 565 mm22.2″ | 595 mm23.4″ | 630 mm24.8″ | 675 mm26.6″ | 720 mm28.3″ | 765 mm30.1″ |
| Saddle height max | 715 mm28.1″ | 745 mm29.3″ | 780 mm30.7″ | 825 mm32.5″ | 870 mm34.3″ | 915 mm36″ |
| Crank length | 165 mm6.5″ | 165 mm6.5″ | 170 mm6.7″ | 170 mm6.7″ | 172.5 mm6.8″ | 172.5 mm6.8″ |
| Stem length | 80 mm3.1″ | 90 mm3.5″ | 90 mm3.5″ | 100 mm3.9″ | 110 mm4.3″ | 120 mm4.7″ |
| Handlebar width | 360 mm14.2″ | 360 mm14.2″ | 360 mm14.2″ | 380 mm15″ | 380 mm15″ | 380 mm15″ |
Side view
Drawn to scale (how to read it).
How the geometry rides
The Nitrogen Pro in size S against the middle size of 65 other bikes: tendencies from geometry, not a ride review (how to read this).
- Wheelbase975 mm38.4″
shortestlonger than 4% of 65 bikeslongest
Short wheelbase: tends to feel more agile in corners and less planted on long straights.
- Chainstay410 mm16.1″
shortestlonger than 63% of 73 bikeslongest
Good to know
Design
Argon 18 claims 23% higher bottom bracket stiffness and 6% higher head tube stiffness than the Sum Pro, with slightly more rear vertical compliance.
SourceCompatibility
Tyres up to 700x32c, measuring no more than 34 mm; rims up to 37 mm external width. Rotors 140 or 160 mm front and rear.
SourceHistory
Launched in September 2025, reviving the Nitrogen name after three years of development; deliveries to dealers were scheduled to start in November 2025. The Nitrogen platform comes in two carbon layups, three colours and six builds.
Source
Nitrogen Pro FAQ
Is the Argon 18 Nitrogen Pro UCI legal?+
Yes. The Argon 18 Nitrogen Pro is UCI legal, so it can be raced in UCI-sanctioned road races.
How much does the Argon 18 Nitrogen Pro cost?+
Manufacturer prices (MSRP): €10,995–€13,995 / $10,499–$14,499 / £9,500–£13,000 across 3 listed builds and framesets: Nitrogen Pro SRAM Red AXS, Nitrogen Pro Shimano Dura-Ace Di2 and Nitrogen Pro Shimano Ultegra Di2.
How much does the Argon 18 Nitrogen Pro weigh?+
The lightest complete build listed (Nitrogen Pro SRAM Red AXS) weighs 6.95 kg (15.3 lb) in size M.
What sizes does the Argon 18 Nitrogen Pro come in?+
6 sizes: XXS, XS, S, M, L and XL.
What is the tire clearance of the Argon 18 Nitrogen Pro?+
Up to 32 mm tires.
Which groupsets are compatible with the Argon 18 Nitrogen Pro?+
Drivetrain compatibility: Electronic groupsets (the assembly guide covers wireless and wired routing only). 2x with 50-57T round chainrings (or oval of equivalent size); 1x up to 56T. 1x drivetrains are supported. The largest chainring that fits is 57T. Bottom bracket: T47 threaded, 85.5 mm shell.
What builds of the Argon 18 Nitrogen Pro are available?+
Nitrogen Pro SRAM Red AXS: SRAM Red AXS E1; Nitrogen Pro Shimano Dura-Ace Di2: Shimano Dura-Ace Di2 R9200; Nitrogen Pro Shimano Ultegra Di2: Shimano Ultegra Di2 R8100.
Is the Argon 18 Nitrogen Pro aerodynamic?+
Argon 18 says the Nitrogen is 24 W faster than its Sum Pro (reported by TOUR; tested with a rider). The white paper claims the CHB-01 cockpit saves 6.7 W against a standard bar and stem and 4.3 W against a Vision Metron 5D at 45 km/h (wind-averaged), the aero cages 1.1 W with bottles and 1.8 W empty, and that adding two bottles costs 0-3 W against 4-9 W on a traditional aero frame. The aero spacers cost 0.7 W per 30 mm of stack (Sum Pro: 1.4 W). (CFD on more than 130 tube profiles and 25 fork prototypes, three wind-tunnel sessions, final tests with a pedalling rider and with mannequin legs at 45 km/h against the Sum Pro and an unnamed WorldTour aero bike. Wheels and frame were developed together with Scope.)
Sources
- https://www.argon18.com/en-us/bikes/road/nitrogen-pro
- https://www.argon18.com/en-us/bikes/road/nitrogen-pro/nitrogen-pro-sram-red
- https://www.argon18.com/en-us/bikes/road/nitrogen-pro/nitrogen-pro-shimano-dura-ace-di2
- https://www.argon18.com/en-us/bikes/road/nitrogen-pro/nitrogen-pro-shimano-ultegra-di2
- https://www.argon18.com/en-dk/bikes/road/nitrogen-pro/nitrogen-pro-sram-red
- https://www.argon18.com/en/bikes/road/nitrogen-pro/nitrogen-pro-sram-red
- https://storage.googleapis.com/argon18craft/files/White-Paper/White-Paper-Nitrogen-Pro.pdf
- https://storage.googleapis.com/argon18craft/files/Assembly-Guides/2025/NITROGEN_NITROGEN-PRO_Assembly-Guide_383A_384A-B_2026-05-05.pdf
- https://www.argon18.com/en-us/stories/argon-18-launches-nitrogen-pro
- https://assets.ctfassets.net/761l7gh5x5an/7jA9krKzzy3lRXPzlm4uyn/7982d7114b9d62978cb87876ea476535/58780c70-6247-4448-8384-b145fa30aba9.pdf
- https://www.tour-magazin.de/en/aero-road-bike/fast-faster-nitrogen-argon-18-challenges-the-aero-frontrunners/
Argon 18 Nitrogen Pro data last updated · How the data is checked ·