the seatpost on my super pista is slipping down as i ride. the seatpost is fine (thompson elite) i can find any problem with the frame, and the bolt tightens fine. does anyone know what would be causing this?

Is your seatpost new? I mean you might have gotten the wrong size post. Other than that, binder bolt might be the reason why you're experience slippage.

You probably got the wrong size seatpost. On my Madison, the seatpost barely fits (27.0)and needs some pushing down abit to get in to where i want. Grease helps. The seatpost shouldnt be able to slide all the way down when you put it on your frame. Also, I tried sizing down (26.8) and it caused some slipping if I didnt tighten it down enough with the seatpost bolt. Anyway, I was just messing around and when i tried to tighten it down more the bolt stripped.... So get the right size seatpost!

Edit: Vix beat me to it

i know its the right sized post, ive put about 500-600 miles on the frame and it just started happening, the post fits pretty tight into the frame. the binder bolt still tightens down and compresses the seat tube. my lbs is closed until monday or i would just have them look at it, any other ideas

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