Quiver

2025 Specialized Aethos LTD vs 2025 Trek Émonda ALR

The 50 is the Trek Émonda ALR size closest to your 52 Specialized Aethos LTD. We match frame stack and reach. This is a geometry comparison, not a fit recommendation; stem, spacers, handlebars and saddle setup also affect your riding position.

What changes on the Trek Émonda ALR

Compared with the Specialized Aethos LTD in 52, the Trek Émonda ALR in 50 places the top of the head tube 6 mm lower and about as far forward, relative to the bottom bracket.

Frame stack
−6 mm
Lower front end
Frame reach
−2 mm
About the same reach
Wheelbase
−1 mm
About the same
Head angle
−0.4°
Slacker: calmer steering
Chainstays
±0 mm
About the same

The two frames

2025 Specialized Aethos LTD (52)The Specialized Aethos LTD frame drawn to scale.J 975

Only the Specialized Aethos LTD is drawn. The Trek Émonda ALR numbers we have for size 50 are missing the seat angle.

Geometry side by side

MeasurementSpecialized Aethos LTD 52Trek Émonda ALR 50Difference
Reach380mm378−2 mm
Stack527mm521−6 mm
Head tube angle72.5°72.1°−0.4°
Seat tube angle74°not listed
Effective top tube531mm521−10 mm
Chainstay length410mm410±0 mm
Wheelbase975mm974−1 mm
BB drop74mm72−2 mm
BB height266mmnot listed
Standover728mm711−17 mm
Seat tube length462mm453−9 mm
Fork length369mmnot listed
Head tube length120mm111−9 mm

Differences are the Trek Émonda ALR minus the Specialized Aethos LTD. Full charts: 2025 Specialized Aethos LTD, 2025 Trek Émonda ALR.

Where each sits in its class

Specialized Aethos LTDTrek Émonda ALR

AggressivePositionUpright
CalmSteeringQuick
PlayfulBalancePlanted

Each bike is ranked against the other road bikes on Quiver, on frame geometry alone. Not your hand position or ride feel.

What each ships with

The stock build of each bike's first listed trim. Parts that match are dimmed.

PartSpecialized Aethos LTDS-Works LTDTrek Émonda ALRALR 5
FrameSpecialized S-Works Aethos FACTnot listed
ShifterSRAM RED AXSnot listed
DerailleurSRAM Red AXSnot listed
CassetteSRAM RED XG-1290not listed
ChainSRAM REDnot listed
CranksetSRAM RED AXS Power Meternot listed
Bottom bracketSRAM DUBnot listed
WheelsetRoval Alpinist CLXBontrager Paradigm SL
TireSpecialized S-Works Turbo 2BRBontrager R1 Hard-Case Lite
BrakeSRAM Red AXSnot listed
StemRoval Alpinistnot listed
SeatpostRoval Alpinistnot listed
SaddleSpecialized S-Works Powernot listed
Forknot listedTrek Émonda ALR

Know what is on every bike.

Add your bike to Quiver. Keep its parts, setup, and service history together, then share your build.

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