Opus Fortitude (rim brakes) (2025)

endurance road · aluminium · sizes XXS–XL Manufacturer’s website

Geometry ?

Opus Fortitude (rim brakes) 2025 geometry in sizes XXS–XL: stack 522–620 mm, reach 366–405 mm, head angle 70.5–72.5°.

	XXS	XS	S	M	L	XL
Stack	522 mm	540 mm	560 mm	580 mm	600 mm	620 mm
Reach	366 mm	370 mm	378 mm	387 mm	396 mm	405 mm
Head angle	70.5°	71°	72.5°	72.5°	72.5°	72.5°
Seat angle	75°	74°	73.5°	73°	73°	72.5°
Seat tube (?)	440 mm	480 mm	520 mm	540 mm	560 mm	580 mm
Head tube	120 mm	135 mm	158 mm	177 mm	198 mm	220 mm
Top tube (effective)	506 mm	525 mm	544 mm	565 mm	580 mm	600 mm
BB drop	75 mm	75 mm	72 mm	72 mm	72 mm	70 mm
Chainstay	412 mm	412 mm	415 mm	415 mm	415 mm	418 mm
Standover	709 mm	736 mm	772 mm	790 mm	810 mm	830 mm
Stock build by size
Cranks	165 mm	170 mm	170 mm	172.5 mm	172.5 mm	175 mm
Stem	70 mm	80 mm	90 mm	100 mm	110 mm	120 mm
Bar width	380 mm	400 mm	420 mm	420 mm	440 mm	460 mm

(?) by the seat tube length: the manufacturer doesn’t say whether it’s measured centre to centre (c-c) or centre to top (c-t).

Source: opusbike.com, checked 7 Nov 2026 · bar position: worked out from published data

Stock build

Fortitude Claris

Source: opusbike.com, checked 7 Nov 2026

Frames with similar geometry

Stack and reach within 12 mm of size M (stack 580 / reach 387 mm).

Spotted a mistake or a missing build? Let me know.

Are you the manufacturer, or do you sell this bike? I’m missing 2 values for this model’s stem and bars. Add them