Compare: 2025 SL8 Specialized Bicycles Tarmac sl8 Pro 165mm vs 2026 XDS X-LAB RT9 Base XS

Insights

Average stack and reach vs trend of performance road bikes

Design deviates from other sizes of Specialized Bicycles Tarmac sl8

Somewhat upright stack and reach vs trend of performance road bikes

Design deviates from other sizes of XDS X-LAB RT9

Stack	501mm	510mm +9mm
Reach	366mm	362mm -4mm
Stack to Reach Ratio	1.37:1	1.41:1
Seat Tube Length, C-T	—	430mm
Seat Tube Length, Unknown	433mm	—
Top Tube Length, Effective/Horizontal Center	496mm	—
Top Tube Length, Effective/Horizontal Unknown	—	498mm
Top Tube Slope	9.8deg	11.3deg +1.5deg
Head Tube Angle	70.5deg	70.5deg +0deg
Seat Tube Angle	75.5deg	75deg -0.5deg
Head Tube Length	99mm	110mm +11mm
Bottom Bracket Drop	74mm	74mm +0mm
Bottom Bracket Height	263mm	265mm +2mm
Chainstay Length	410mm	410mm +0mm
Chainstay Length Horizontal	403.3mm	403.3mm +0mm
Front-Center	572mm	574mm +2mm
Front-Center Horizontal	566.7mm	569.2mm +2.5mm
Wheelbase	970mm	972.5mm +2.5mm
Fork Offset/Rake	46.7mm	49.8mm +3.1mm
Fork Length, Unknown	370mm	—
Trail	69.8mm high	67.2mm -2.6mm high
Mechanical Trail	65.8mm	63.4mm -2.4mm
Wheel Flop	22mm	21.2mm -0.8mm
Standover Height	723mm	704mm -19mm
Tire to Pedal Spindle	65mm 170 mm cranks	65mm +0mm 170 mm cranks
Pedal Spindle to Ground Clearance	93mm 170 mm cranks	95mm +2mm 170 mm cranks

Wheel Size	700C/29 in 622 mm BSD	700C/29 in 622 mm BSD
Tire Width	26mm	28mm +2mm
Tire Outer Diameter	674mm	678mm +4mm
Bike Length with Tires	1644mm	1650.5mm +6.5mm
Handlebar Width	380mm	—
Stem Length	75mm	—
Suspension Type	Rigid, non-suspension corrected	Rigid, non-suspension corrected
Bar Type	Drop Bar	Drop Bar
Frame Material	Carbon/Composite	Carbon/Composite
Fork Material	Carbon/Composite	Carbon/Composite
Brake Type	Disc	Disc