Tarmac SL8 (2024) vs. Madone SL Gen 8 (2025)

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

Cockpit: 20 mm spacers · 100 mm stem · -6°

SpacersStemAngle °

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

Saddle heightSetbackForward (+)/back

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

Cockpit: 20 mm spacers · 100 mm stem · -6°

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

Madone SL Gen 8 (2025) M vs. Tarmac SL8 (2024) 54: 0.4° slacker seat angle

Measure	Tarmac SL8 (2024) 54	Madone SL Gen 8 (2025) M
Frame
Stackmm	544	546+2
Reachmm	384	384±0
Stack / Reach	1.42	1.42+0.01
Head angle°	73.0°	72.9°−0.1°
Seat angle°	74.0°	73.6°−0.4°
Head tubemm	137	136−1
Seat tubemm	473	476+3
Top tube (effective)mm	541	545+4
Chainstaymm	410	410±0
Rear centre (horizontal)mm	404	404±0
Wheelbasemm	978	981+3
Front centremm	579	582+3
BB dropmm	72	70−2
BB heightmm	268	269+1
Fork offsetmm	44	45+1
Trailmm	58	58±0
Fork axle-to-crownmm	370	–
Cockpit & riding position
Bar reachmm	470	470±0
Bar stackmm	601	603+2
Saddle – barmm	669	674+5
Saddle-to-bar dropmm	91	87−4

italic = calculated · tap a row to pin the measure in the drawing · Δ relative to Tarmac SL8 (2024)

Size finder · transfer your fit

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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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All frame sizes at a glance

All frame sizes by stack and reach or any other measure – click a dot or line to add the bike to the comparison.

1040 of 1040 sizes · 159 models

Each dot is a frame size. Coloured dots with a letter = current comparison.

Similar to Tarmac SL8 (2024) 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

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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