Hi -
you first need to host your pics on a public domain (note - sites like Yahoo & Imagestation will not allow direct links from another site however);
you can request a gallery here on TriumphNet - follow instruction under Member-Maintained Albums - Vol 2 at
click here for photo albums
Or you can request an album at
www.bikepics.com for this purpose also.
Once you have your pics uploaded to a public domain, then you get the URL link of the particular picture you want to display in your post (right-click on the pic & check the properties) and embed it in your message - the simplest way is just to use the "image" icon (located below the field in which you are constructing your message) and paste the link in the prompt box.