To attach an image:
1) Begin a reply to this thread (click on "post quick reply")
2) Choose the third icon from the left which is shown above the dialog box where you type. This icon is a small square with tree or something just next to the globe with a red X.

OR

Sign up with an image hosting site like flickr.com . It is a longer process but will allow you to show large pictures along with the text.
to do so:
1) Form a flickr account at <flickr.com> . (It is like signing up for an email account)
2) Upload photos from your computer by clicking the upload button (slightly to the right at the top of the page)
3) Click on "share" (top left just below "organize and create"
4) Copy and paste the HTML code into your bike forums posting.