The problem with hosting photos on another site is that there is less control over those photos. So it is not uncommon to have someone pull up an old page where all the remotely hosted photos are missing.
There is a trick to making photos hosted on BikeForums bigger.
- Insert your image.
- Go to a preview page and open the link in a new window.
- Copy the URL from this new page, and paste it back into your document surrounded by [img] and [/img]
You will end up with both the thumbnail and the big photo.