Ducati SPORT 1000 Manuel D'utilisation page 105

At the rear end of the frame underneath the seat, there are
the helmet hook (4, fig. 23.1 - fig. 23.2) for rider helmet. 4
Hook the helmet strap onto the hook and leave the helmet
hanging outside. It will be locked safely when you refit the
seat.
Warning
This system is intended to lock your helmet safely
when you park your motorcycle. Never leave the helmet
E hanging from the hook when riding or it may get in the way
and make you lose control of the motorcycle.
Closing
Make sure that all parts are arranged and secured properly
fig. 23.2
inside the compartment under the seat. Slide the seat
retainers (2, fig. 22) into the frame hooks (3, fig. 23.1) and
push down on the rear end of the seat until you hear the
catch click. Make sure the seat is firmly secured to the
frame and take the key out of the lock (1, fig. 22).
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