Some people make them flash like that it is not a requirement, just something people do to bring more attention to their braking.
It may be fine for the USA but I can imagine an army of EU bureaucrats and the UK agencies all getting themselves into compliance meltdown over that sort of 'innovation'. No we don't want any of that sort of non-compliance here!Its a common mod. But surprisingly that feature is STOCK on the BMW s1000rr in the USA at least.
hooligan 4 life