If you are looking to post your web site - Go to your Profile - add a title for your web page and then paste the web page address into Website URL - so if you wanted one of your pictures like
http://bikepics.com/pictures/084909/ on there, you would put what you wanted in the Website Title box and then the URL into the Website URL box.
If you are looking to post a picture of your bike under your name (as stated) then you need to put the URL into the "I have my own picture" box and click the small box to the left of that. I don't know but believe it will get rid of the bobafett picture you have.