Masters Of Speed

Our good friend "the German" has uncovered a stunning piece of secret history when working on his latest project; I can't tell you what bike that is yet, but what I can tell you is that it will rule over countless miles of open road on an Avon Speedmaster front tire. Now look what the man himself is wearing on his wrist:

As I'm sure you know, the Omega Speedmaster is NASA's standard issue watch, rigorously tested, flown in space and worn on the moon. It seems pretty obvious then, that the Avon Speedmaster was being used on the moon as well, probably on a lunar racetrack where NASA astronauts competed against Martians and other extraterrestrials for the coveted Sol cup, the most prestigious award in interplanetary motorcycle racing.
Are there Nortons still on the moon, or did they bring them back? Where are they?