<p>The invention relates to a system for protecting motorcyclists, consisting of a continuous lower barrier that closes off the space beneath an upper barrier that is attached to ground-anchoring posts (1) by means of spacers (2). According to said system, the continuous lower barrier is installed using post arms (6) and/or intermediate arms (7), each post arm (6) comprising a single sheet metal part with a stepped profile having an upper tab or expansion, by means of which each post arm (6) is attached directly to the corresponding post (1) without any parts of the installed barrier having to be disengaged or adjusted.</p>
