Quiver

2026 Specialized Tarmac SL8 Pro Shimano vs 2027 Trek Madone SLR Gen 8 No. ICON

The XS is the Trek Madone SLR Gen 8 No. ICON size closest to your 49 Specialized Tarmac SL8 Pro Shimano. 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 Madone SLR Gen 8 No. ICON

Compared with the Specialized Tarmac SL8 Pro Shimano in 49, the Trek Madone SLR Gen 8 No. ICON in XS places the top of the head tube 7 mm lower and 5 mm further back, relative to the bottom bracket.

Frame stack
−7 mm
Lower front end
Frame reach
−5 mm
Shorter frame reach
Wheelbase
−2 mm
About the same
Head angle
n/a
One of the bikes has no number for this
Chainstays
±0 mm
About the same

The two frames

We can't draw these frames yet. The Specialized Tarmac SL8 Pro Shimano numbers we have for size 49 are missing the head angle. The numbers below still compare.

Geometry side by side

MeasurementSpecialized Tarmac SL8 Pro Shimano 49Trek Madone SLR Gen 8 No. ICON XSDifference
Reach375370−5 mm
Stack514507−7 mm
Head tube anglenot listed71.6°
Seat tube angle75.5not listed
Chainstay length410410±0 mm
Wheelbase973971−2 mm
Head tube length109100−9 mm
Effective top tubenot listed517
BB dropnot listed72
Standovernot listed704
Seat tube lengthnot listed404

Differences are the Trek Madone SLR Gen 8 No. ICON minus the Specialized Tarmac SL8 Pro Shimano. Full charts: 2026 Specialized Tarmac SL8 Pro Shimano, 2027 Trek Madone SLR Gen 8 No. ICON.

Where each sits in its class

Specialized Tarmac SL8 Pro ShimanoTrek Madone SLR Gen 8 No. ICON

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 Tarmac SL8 Pro ShimanoPro - Shimano Ultegra Di2Trek Madone SLR Gen 8 No. ICONSLR 9 AXS Gen 8 - No. 76 ICON
FrameSpecialized Tarmac SL8not listed
ForkSpecialized FACT 10rTrek Madone Gen 8 one-piece
ShifterShimano Ultegra R8170SRAM RED AXS E1
DerailleurShimano Ultegra R8150 Di2SRAM RED AXS E1
CassetteShimano UltegraSRAM RED XG-1290 E1
ChainShimano XT M8100SRAM Red E1
CranksetShimano Ultegra R81000SRAM RED AXS E1
Bottom bracketShimano Threaded BSASRAM DUB
WheelsetRoval Rapide CL IIIBontrager Aeolus RSL
TireSpecialized S-Works TurboBontrager Aeolus RSL RD
BrakeShimano Ultegra R8170not listed
RotorShimano Ultegra R8170SRAM Paceline
HandlebarRoval Rapide Cockpitnot listed
StemRoval Rapide Cockpitnot listed
Bar tapeSupacaz Super Sticky Kushnot listed
SeatpostSpecialized S-Works Tarmac SL8Trek Madone
SaddleSpecialized Power ProTrek Aeolus RSL
Batterynot listedSRAM AXS
Headsetnot listedBontrager Expander Plug

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