You might be looking at the 'Active Topics' page. Posts disapear from there if no replies have come in since the last time you visited (or any other time frame you select). Your post is within the forum 'Anything Goes'. if you are looking for a post you made and you are not sure where to find it (might have been moved to the appropriate forum by a moderator) simply see your member link (the one that you get when you click on a members name) You will find links to the last 10 topics you have posted no matter what forum they are in.
Hope this helps!
BTW: Nice bike you got there. I like your large filter on the right side.