Originally Posted by
maddog34
this one was cut down pretty far... appears the bottom of the seat post became an issue, or it slipped upward before the pic was taken... the gap at the top of the frame tube is usually just about 1/4-3/8 inch in the other pics i found, so.....
http://thumbs.ebaystatic.com/d/l400/...69135988_1.jpg
the main structural issue would be post/frame interface length, and related stresses, getting to the point of seat tube failure, i'd think.... limiting factors as far as obstruction have already been discussed above.
how much do you weigh? how thick is that seat tube? how long is the seat tube now? and is your seat going to be adjusted very far towards the rear of the bike?
have you ever bent seat rails? it happens sometimes...
It is hard to tell from that photo whether the black area between the top of the seat tube and the Epost isn't just a spacer. It could also be that the owner installed the black elastomer instead of the red or grey one. The Epost allows 3 cm of fore and aft movement of the saddle clamp itself without having to move the saddle rails in the clamp. You would almost never have to move the saddle in the clamp to be able to move it back sufficiently