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Specialized Tarmac SL8 2024
Bastion Road 2017 ×
Bastion Road 2016 ×
Overlay
Stack and reach
Bike geometry overlay
Wireframe side views of compared bikes aligned at the bottom bracket. Hover a frame to isolate it, or a measurement to see it drawn from its origin.
Some tubes use estimated defaults where OEM values were missing.
Geometry by size
Measurement
Bastion
Road 2017
51
54
56
58
Bastion
Road 2016
51
54
56
58
Stack
mm
564
564
Reach
mm
394
394
Head tube angle
°
73.2
73.2
Seat tube angle
°
73.5
73.5
Chainstay
mm
408
408
Wheelbase
mm
994
994
BB drop
mm
70
70
BB height
mm
—
—
Standover
mm
—
—
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Relaxed/Aggressiveness
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Road · 56
Road · 56
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Specialized Tarmac SL8 2025
Near Bastion Road · 52 · 527 mm / 380 mm
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Specialized Tarmac SL8 2024
Near Bastion Road · 52 · 527 mm / 380 mm
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Specialized Tarmac SL8 2026
Near Bastion Road · 52 · 527 mm / 380 mm
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Cockpit for the selected size
Part
Road 56
Road 56
Stem
100 mm
100 mm
Bar
420 mm
420 mm
Crank
172.5 mm
172.5 mm
