Argon 18 Dark Matter 2026: geometry, stack and reach

Geometry ?

Argon 18 Dark Matter 2026 geometry in sizes XXS–XL: stack 520–629 mm, reach 370–430 mm, head angle 68.5–71°.

	XXS	XS	S	M	L	XL
Stack	520 mm	540 mm	561 mm	582 mm	603 mm	629 mm
Reach	370 mm	382 mm	394 mm	406 mm	418 mm	430 mm
Head angle	68.5°	70°	70.5°	71°	71°	71°
Seat angle	75.5°	74.9°	74.3°	73.7°	73.1°	72.5°
Seat tube (c-t)	420 mm	435 mm	460 mm	495 mm	540 mm	585 mm
Head tube	72 mm	87 mm	106 mm	126 mm	151 mm	178 mm
Top tube (effective)	507 mm	530 mm	553 mm	577 mm	602 mm	629 mm
BB drop	80 mm	80 mm	78 mm	78 mm	76 mm	76 mm
Chainstay	436 mm	436 mm	436 mm	436 mm	436 mm	436 mm
Wheelbase	1030 mm	1036 mm	1045 mm	1059 mm	1080 mm	1101 mm
Standover	713 mm	729 mm	755 mm	786 mm	825 mm	863 mm
Fork length	425 mm	425 mm	425 mm	425 mm	425 mm	425 mm
Fork offset	54 mm	54 mm	48 mm	48 mm	48 mm	48 mm
Stock build by size
Cranks Dark Matter SRAM Force XPLR AXS	160 mm	165 mm	170 mm	170 mm	172.5 mm	172.5 mm
Cranks Dark Matter Shimano GRX RX610/822	165 mm	165 mm	170 mm	170 mm	172.5 mm	172.5 mm
Stem	60 mm	70 mm	80 mm	90 mm	100 mm	110 mm
Bar width	420 mm	420 mm	420 mm	420 mm	420 mm	440 mm

Source: argon18.com, checked 1 Nov 2026 · bar position: worked out from published data

An older model year in the archive with the same stack, reach and head angle: 2025. Source: storage.googleapis.com

Stock build

Dark Matter SRAM Force XPLR AXS €7,395

Dark Matter SRAM Rival XPLR AXS €5,095

Dark Matter Shimano GRX RX610/822 €3,995

Source for all builds: argon18.com, checked 1 Nov 2026

Frames with similar geometry

Stack and reach within 12 mm of size M (stack 582 / reach 406 mm).

Argon 18 Dark Matter (2026)