gravel bike•race geometry•2025
Argon 18 Dark Matter Geometry & Size Chart
Argon 18 Dark Matter geometry (2025), compare stack, reach, and every supported size, then open the TrainCraft calculator with this bike preselected.
- Supported sizes
- XXS, XS, S, M, L, XL
- Family
- This bike leans toward an aggressive front end, faster steering, and a more performance-oriented position.
- What to compare
- Use this guide to compare stack, reach, and gravel-specific front-end assumptions before choosing a frame size.
Quick size check
What Argon 18 Dark Matter size fits you?
Get an instant frame estimate, then continue into the full fit report to check cockpit reach, bar drop, and setup risks before you buy.
Your measurements have been calculated for this bike. Exact sizes, rankings, setup numbers and risk details are ready in the full report.
Calculating…
No account needed for this check. The full report keeps this bike preselected.
What you get after the size check
A complete setup now. A Fit Passport when you sign up.
A paid report unlocks the complete setup and print-ready PDF for this bike. No account is required. Create a free fit profile separately to save and reuse your fit.
Paid report for this bike
Compare every size and get saddle position, cockpit coordinates, stem, spacers, bar width and crank length. No account required.
Print-ready PDF included
Export the paid report as a clean A4 PDF to keep, print or take into the workshop when this bike is being set up.
Free Fit Passport for ongoing fitting
Create a free fit profile to save measurements and reports across devices, prefill new fits, recalculate after profile changes, fine-tune by symptoms and get the lower in-app report price.
Geometry and size breakdown
Use the geometry table as context, then enter your measurements above before opening the full fit report.
| Size | Stack | Reach | Top tube | Head tube | Stem | Crank | Size check |
|---|---|---|---|---|---|---|---|
| XXS | 520 mm | 370 mm | 507 mm | 72 mm | 60 mm | 160 mm | Check with my measurements |
| XS | 540 mm | 382 mm | 530 mm | 87 mm | 70 mm | 165 mm | Check with my measurements |
| S | 561 mm | 394 mm | 553 mm | 106 mm | 80 mm | 170 mm | Check with my measurements |
| M | 582 mm | 406 mm | 577 mm | 126 mm | 90 mm | 170 mm | Check with my measurements |
| L | 603 mm | 418 mm | 602 mm | 151 mm | 100 mm | 172.5 mm | Check with my measurements |
| XL | 629 mm | 430 mm | 629 mm | 178 mm | 110 mm | 172.5 mm | Check with my measurements |
How to use this guide
Start with the size table to narrow the geometry range you actually want. Then open the calculator to compare that geometry against your body dimensions, flexibility, and fit priorities.
The TrainCraft bike fit tool models saddle height, cockpit reach, and bar drop using the frame geometry plus stock cockpit assumptions for the Argon 18 Dark Matter.
That is more useful than a generic height chart because two sizes can both fit your height while requiring very different stems, spacers, or saddle positions.
Looking at other Argon 18 bikes? Argon 18 sets frame sizes model by model. Argon 18 size calculator →
FAQ
- What size Argon 18 Dark Matter should I get?
- It depends on more than your height. Two riders of the same height can need different Argon 18 Dark Matter sizes, because inseam, torso length and flexibility change the reach and bar drop that suit them. Enter your height and inseam in the size check on this page to see which size fits you.
- What height is each Argon 18 Dark Matter size for?
- Height ranges are only a rough guide: they overlap, and riders near the edge of a range often fit the next size better. The size check on this page uses your height and inseam to show where you land on the Argon 18 Dark Matter.
- Should I size up or down on the Argon 18 Dark Matter?
- Between two sizes, the smaller frame usually needs a longer stem and more spacers, and the larger one a shorter stem and a lower front. Which one works depends on your body and flexibility. The size check shows your size; the full fit gives the exact setup that size needs.
- What sizes are available for the Argon 18 Dark Matter?
- TrainCraft currently tracks these Argon 18 Dark Matter sizes: XXS, XS, S, M, L, XL. The calculator uses each size's published geometry and stock cockpit assumptions to compare fit outcomes.
Rivals to put next to the Argon 18 Dark Matter
Matched sizes, stack and reach deltas, and a fit check for your measurements on both frames.
Related gravel bike guides
Use nearby model pages to compare positioning trends before choosing between similar bikes.
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