These pictures are wayyyy too big for most monitors.
The picture you uploaded is about 3 to 4 screens wide on my 1024*768 screen (12" laptop, any higher resolution would be a pain to use), so even on a 1280*1024 monitor (the most common resolution nowadays), we can't even see a quarter of the wheel.
Besides, it ruins the formatting of the page, as we have to keep scrolling left and right to read each post.
Use IrFanView or the GIMP (both are free) to resize your images before uploading them, if you do not own any image-editing software yet.