Repair guides › Seat & Contact
Pull, clean and grease seatpost
Holds the saddle and sets saddle height. Diameter must exactly match the frame (27.2, 30.9 and 31.6 mm are common; it is printed on the post). Slides into the seat tube; the seat clamp squeezes the tube onto it. The minimum-insertion line must stay inside the frame, and the post must reach below the top-tube/seat-stay joint. 27.2 mm is the most common size, so dropper and suspension posts are easy to find.
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Tools
- Ball-end hex key set (1.5–10 mm): Park Tool HXS-1.2 Professional L-Shaped Hex Set ($$)
- Tape measure + 6" steel ruler: Stanley 16 ft tape measure ($)
- Shop rags + nitrile gloves: shop towels and nitrile gloves ($)
- Bike grease: Park Tool PPL-1 PolyLube 1000 ($)
- Carbon assembly paste: Park Tool SAC-2 SuperGrip Carbon and Alloy Compound ($)
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Steps
- Mark the height with tape.
- Loosen and twist the post out.
- Clean post and inside the seat tube.
- Thin coat of grease inside the seat tube (carbon post or frame: carbon assembly paste, no grease), reinstall at the mark.
Diagram
Side view, chain side toward youSeatpost and saddle
Signs it needs doing
- Post slips down while riding
- Creak from the seat area
- Stuck post (corrosion)