Well it's not supposed to telescope. I got a new used frame (steel), swapped my components from my old frame, rode it a little bit and a few blocks from home the seatpost telescopes. (Slides as far down as it would go.) When I got home I tightend the bolt as much as I thought I could get away with. I always read that you should put a very thin coating of grease on the seatpost so it won't rust and get frozen in position so when I built the bike that is what I did. I went out Sunday afternoon for a longer ride and a few miles from home I miss a pedal and the impact telescopes the seat post again. Tonight I pulled the seat post out, cleaned out the inside of the seat tube and the outside of the stem with rags and acetone. I put it back together and again tightened it as much as I thought I could get away with. Tomorrow I'll check it out again. This time I marked the position on the post with a marker so if I have to make emergency adjustments on the road I can get it back to where it was.