Unhook the spring clips (1) on both sides of the filter box.
Remove the cover.
Remove the filter cartridge.
At reassembly, fit the cartridge with the fins pointing forwards in the direction of travel.
Loosen the clips (2) on the manifold hoses between the filter box and the throttle body.
Loosen the clip and disconnect the filter box tube from the oil breather tank.
Unscrew the 2 rear screws (4) holding the filter box to the frame cross member.
Unscrew the screws (5) holding the front of the filter box to the frame.
Raise and remove the filter box complete with its drain hose.
At reassembly, ensure that the marks (A) and (B) on the manifold hose and on the filter box are aligned with each other.