Ducati ST3 Owner's Manual page 181

Lifting the fuel tank
Unscrew the 2 screws (1, fig. 69) that hold the cover to the
tank support. Remove the cover sliding it off the ignition
switch. Pull and lift the clip (2, fig. 68) off the tank support.
Lift the tank and unhook the support rod (3, fig. 70). Rest
the tank onto the rod as shown in the figure.
When you are finished, reverse the above procedure to
refit all the parts you have removed.
E
Warning
Make sure the fuel in the tank is less than 6 litres (the
fuel warning light on the instrument panel should be on) or
fuel may leak out through the filler plug breather.
72
1
fig. 69
2
fig. 68
3
fig. 70