
Specialized Narrow Carbon Steerer Expander Plug OEM Aethos 2
Specialized Narrow Carbon Steerer Expander Plug OEM Aethos 2
Stage 21 Bikes
23582 Moulton Parkway
#111
Laguna Woods CA 92637
United States
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Specialized Factory Replacement Narrow Carbon Steerer Tube Expander Plug
This Specialized factory replacement steerer tube expander plug is designed specifically for carbon forks with a narrow internal diameter, as used on 2026 Aethos 2 platform bikes. It provides proper headset preload while safely expanding inside the carbon steerer without damage.
This is a model-specific OEM part and is not cross-compatible with aftermarket compression plugs or forks not originally equipped with this design from the factory.
Correct installation orientation and torque are critical for safe use.
Key Features & Benefits
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Genuine Specialized OEM replacement
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Designed for narrow-ID carbon steerer tubes
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Lightweight alloy construction
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Provides secure headset preload without steerer damage
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Factory-correct fit for Aethos 2 carbon forks
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Maintains Specialized warranty and safety specifications
Technical Specifications
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Application: Carbon fork steerer tube compression
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Steerer Type: Narrow internal diameter carbon steerer
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Length: 50 mm
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Outer Diameter: 22.4 mm
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Top Cap Bolt Compatibility: M6 × 1.0 pitch
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Torque Spec: 9 Nm (79.6 in-lbf)
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Material: Lightweight alloy
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Orientation: Arrow must face forward during installation
Important Compatibility Notes
⚠️ Factory-Installed Use Only
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Approved only for bikes originally equipped with this expander plug
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Not compatible with aftermarket compression plugs
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Not compatible with forks using standard/wide ID steerer plugs
Improper substitution may result in headset preload failure or steerer damage.
OEM Compatibility
2026 Specialized Aethos 2 Platform
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S-Works Aethos 2 Frameset – FACT 12r Carbon
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S-Works Aethos 2 – Shimano Dura-Ace Di2
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S-Works Aethos 2 – SRAM RED AXS
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Aethos 2 Pro – Shimano Ultegra Di2
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Aethos 2 Pro – SRAM Force AXS
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Aethos 2 Frameset – FACT 10r Carbon
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Aethos 2 Expert – Shimano Ultegra Di2
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Aethos 2 Expert – SRAM Force AXS
Installation Notes
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Install with arrow pointing toward the front of the bike
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Use only with M6 top-cap bolts
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Torque to 9 Nm maximum
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For carbon steerer tubes only
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Professional installation recommended
Why Use OEM?
Using the correct Specialized compression plug ensures:
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Safe headset preload
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Proper carbon steerer support
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Elimination of creaks or play
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Preserved fork integrity
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Factory-correct fit and finish
The only correct OEM narrow-ID steerer expander plug for 2026 Specialized Aethos 2 carbon forks.


