Quiver

2027 Trek Madone SLR Gen 8 First ICON vs 2026 Specialized Tarmac SL8 Pro Shimano

The 49 is the Specialized Tarmac SL8 Pro Shimano size closest to your XS Trek Madone SLR Gen 8 First ICON. 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 Specialized Tarmac SL8 Pro Shimano

Compared with the Trek Madone SLR Gen 8 First ICON in XS, the Specialized Tarmac SL8 Pro Shimano in 49 places the top of the head tube 7 mm higher and 5 mm further forward, relative to the bottom bracket.

Frame stack
+7 mm
Higher front end
Frame reach
+5 mm
Longer 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 Trek Madone SLR Gen 8 First ICON numbers we have for size XS are missing the seat angle. The numbers below still compare.

Geometry side by side

MeasurementTrek Madone SLR Gen 8 First ICON XSSpecialized Tarmac SL8 Pro Shimano 49Difference
Reach370375+5 mm
Stack507514+7 mm
Head tube angle71.6°not listed
Effective top tube517not listed
Chainstay length410410±0 mm
Wheelbase971973+2 mm
BB drop72not listed
Standover704not listed
Seat tube length404not listed
Head tube length100109+9 mm
Seat tube anglenot listed75.5

Differences are the Specialized Tarmac SL8 Pro Shimano minus the Trek Madone SLR Gen 8 First ICON. Full charts: 2027 Trek Madone SLR Gen 8 First ICON, 2026 Specialized Tarmac SL8 Pro Shimano.

Where each sits in its class

Trek Madone SLR Gen 8 First ICONSpecialized Tarmac SL8 Pro Shimano

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.

PartTrek Madone SLR Gen 8 First ICONSLR 9 AXS Gen 8 - The First 50 ICONSpecialized Tarmac SL8 Pro ShimanoPro - Shimano Ultegra Di2
ForkTrek Madone Gen 8 one-pieceSpecialized FACT 10r
ShifterSRAM RED AXS E1Shimano Ultegra R8170
DerailleurSRAM RED AXS E1Shimano Ultegra R8150 Di2
CassetteSRAM RED XG-1290 E1Shimano Ultegra
ChainSRAM Red E1Shimano XT M8100
CranksetSRAM RED AXS E1Shimano Ultegra R81000
Bottom bracketSRAM DUBShimano Threaded BSA
BatterySRAM AXSnot listed
WheelsetBontrager Aeolus RSLRoval Rapide CL III
TirePirelli P ZeroSpecialized S-Works Turbo
RotorSRAM PacelineShimano Ultegra R8170
HeadsetBontrager Expander Plugnot listed
SeatpostTrek MadoneSpecialized S-Works Tarmac SL8
SaddleTrek Aeolus RSLSpecialized Power Pro
Framenot listedSpecialized Tarmac SL8
Brakenot listedShimano Ultegra R8170
Handlebarnot listedRoval Rapide Cockpit
Stemnot listedRoval Rapide Cockpit
Bar tapenot listedSupacaz Super Sticky Kush

Know what is on every bike.

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

Explore the app
A Transition Relay build sheet: frame, fork, shock and drivetrainThe Relay’s ride photo galleryThe Relay’s ride spectrum and 2D frame geometryThe garage: five bikes and 99 recorded partsA Specialized Tarmac SL8 road build sheet