Specialized Aethos (2021–2025) – geometry

Name: Specialized Aethos (2021–2025)
Brand: Specialized

Specialized · Road · 700cManufacturer data · as of Oct 25, 2026Source

Cockpit: 20 mm spacers · 100 mm stem · -6° (stock)

SpacersStemAngle °

Saddle: same saddle height · 0 mm setback · centred (default)

Saddle heightSetbackForward (+)/back

Reach: Horizontal distance from the bottom bracket to the top of the head tube. More reach = more stretched-out position. · grid 10 cm

Measure	Aethos (2021–2025) 54
Frame
Stackmm	544
Reachmm	384
Stack / Reach	1.42
Head angle°	73.0°
Seat angle°	74.0°
Head tubemm	137
Seat tubemm	481
Top tube (effective)mm	540
Chainstaymm	410
Rear centre (horizontal)mm	404
Wheelbasemm	978
Front centremm	579
BB dropmm	72
BB heightmm	268
Fork offsetmm	44
Trailmm	58
Fork axle-to-crownmm	369
Cockpit & riding position
Bar reachmm	470
Bar stackmm	601
Saddle – barmm	669
Saddle-to-bar dropmm	91

italic = calculated · tap a row to pin the measure in the drawing · Δ relative to Aethos (2021–2025)

Geometry table Specialized Aethos (2021–2025)

Road · 700c · Sizes 49–61 · Stack 514–612 mm · Reach 375–408 mm · Head angle 71.8–74.0°

Measure	49	52	54	56	58	61
Stackmm	514	527	544	565	591	612
Reachmm	375	380	384	395	402	408
Stack / Reach	1.37	1.39	1.42	1.43	1.47	1.50
Head angle°	71.8°	72.5°	73.0°	73.5°	73.5°	74.0°
Seat angle°	75.5°	74.0°	74.0°	73.5°	73.5°	73.0°
Head tubemm	109	120	137	157	184	204
Seat tubemm	431	462	481	504	532	567
Top tube (effective)mm	508	531	540	562	577	595
Chainstaymm	410	410	410	410	410	410
Rear centre (horizontal)mm	403	403	404	404	404	404
Wheelbasemm	973	975	978	991	1005	1012
Front centremm	574	577	579	591	606	613
BB dropmm	74	74	72	72	72	72
BB heightmm	266	266	268	268	268	268
Fork offsetmm	47	47	44	44	44	44
Trailmm	63	58	58	55	55	52
Fork axle-to-crownmm	369	369	369	369	369	369

italic = calculated from the other values · Source: Geometry table Specialized, as of Oct 25, 2026

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Enter your well-fitting bike with saddle height, seatpost and cockpit. For every size of the new bike we calculate the stem, spacers, saddle height, setback and saddle position that reproduce the same contact points. This is a geometric approximation without guarantee and does not replace a professional bike fit.

Your bike – how you sit today

Saddle

mmmmmm

Cockpit

mmmm°

Saddle: 198 mm behind · 692 mm above BB
Handlebar: 470 mm ahead · 601 mm above BB
Saddle–bar: 669 mm · drop 91 mm

Saddle height: bottom bracket centre to top of saddle along the seat-tube axis. Saddle fore/aft: + forward, − back. Spacers incl. top cap, handlebar centre = stem clamp.

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1040 of 1040 sizes · 159 models

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Similar to Aethos (2021–2025) 54

only Road

Similarity over the axes of the geometry profile below; stack and reach count 1.5×. The best-matching size per model, filters are respected.

Geometry profile

Each line is a frame size across all selected measures. Drag on an axis to filter a range – this also affects the chart and the similarity list.

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BrandModelModel year *CategoryWheel (front)Wheel rearTyre clearance, max. (mm)Source (manufacturer page with geometry table) *

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Select the table on the manufacturer's page, copy it and paste it here. Sizes as columns or rows, German or English; values like “435/432” for flip chips are recognised.

Sizes (mm / degrees · * required · setting e.g. “High”, “Low”, “Mullet”)

Size*	Setting	Stack*	Reach*	Head ∠ °*	Seat ∠ °*	Head tube*	Chainstay*	BB drop*	BB drop rear	Seat tube	Top tube	Wheelbase	Fork offset	Axle-to-crown	BB height	Front ctr.	Trail	Stem	Spacers

Specialized Aethos (2021–2025) – geometry

Similar geometry

Similar to Aethos (2021–2025) 54

Geometry profile