Originally Posted by
datlas
The size info is typically at the bottom of the seatpost, below the “min insert” line. So although it’s a nuisance to fully remove it, the info you seek should be there. You can always add some friction paste to reduce slippage.
grumble grumble grumble. My ritchey breakaway clamp is 31.6 mm and my seat post is smaller than that so I’m going to just guess and say it’s 27 mm.
No bike shop in my area carries carbon paste, and I hate ordering things online.