I see the Flickr link embedded in the page source code. But you may need to use Flickr's preferred sharing code -- shown below.
In response to complaints about copyright violations Flickr obscures the URLs for the actual image. This makes it difficult to just right click to obtain the image source code.
IMG_20170907_154846535 by
Robert Hudson, on Flickr
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The workaround is to use Flickr's preferred BB code, then isolate the URL for the JPEG and paste it into Bike Forum's "insert image" prompt. Like this...
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