Back in the day, the English sold quite a lot of opium in China, but weren't so keen on its being consumed back home. Perhaps the Japanese have taken a leaf out of their book.
I reckon you'd just put it on for the shakken (Japanese MoT) every 2 years, then ride around in 2nd gear revving the nuts off the poor girl for the rest of the time.. Having lived in Japan for 4 years that seems to be what most bikers do My 748 is going with me if I ever go back there to live.
Nasty! I suppose it distracts from the number plate holder. Not much point trying to neaten the back end up with a tail tidy when you've got that big wanger hanging out the back!