I'd go with gary there. Probably put in to power some heated clothing or some such! See if you can find someone nearby with hella plugs to see if they are working, r wet your finger and stick it in!!
The hanging socket is almost certainly for connecting a battery charger, the fixed sockets are usually for accessories such as heated clothing.
Cheers guys. I traced the plug hanging down and it goes straight to the battery. The two other plugs look similar to the old computer mouse/keyboard sockets Maybe now I can email on the move!! Ryan
The hanging socket looks exactly the same as the one on my Oxford optimiser. But, I changed mine to plug straight I to the hela socket behind the left hand fairing at knee height.