The motorcycle first appeared in The Foundry, while Dean was walking back to the Impala after purchasing food from a store. He gave a comment of appreciation, unaware on who it truly belonged to. Mr. Ketch is revealed to be following the Winchester brothers using this motorcycle, and in American Nightmare, he follows them to Mason City, Iowa.
After the brothers let the psychic Magda Peterson go, Mr. Ketch follows her into the bathroom and kills her, while bemoaning the Winchester brothers inability to "finish the job".
The motorcycle's license plate is GK B02.
While Arthur drives a car for several episodes, in The Raid he uses his motorcycle to visit Dean at the Men of Letters bunker. Arthur continues to use the motorcycle when the two men go after a vampire nest together and then rush back to the British Men of Letters compound.
It is unknown what ultimately happened to the motorcycle following Arthur's death in Who We Are. If it was still inside the British Men of Letters compound, it was presumably destroyed in the explosion.