I have about 135mm outside and around 85-88mm inside the frame the post is a 27.2mm carbon in alloy frame. It goes about 30mm bellow the bottom of the top tube. To my memory as long as it goes seat post diameter below it should be ok?. Also i weight about 145-150 threw out the year if that matters. Not sure how to post a pic on a moblie will try when i get on the pc