Usa models are equipped with an additional system with an evaporative emissions canister that prevents fuel fumes from being discharged into the atmosphere.
The breather hose (4) is connected to the canister filter (1); when the fuel has been filtered, it is returned through the hose (2) to the horizontal (a) and vertical (b) intake manifolds via the hoses (2a) and (2b). Drainage pipe (c) and the hose (5) vent to the ground.
For correct positioning of the connection hoses consult the indications given below.

Evaporative emissions canister
Removal of the evaporative emissions canisterRemoval of the fuel tank filler cap
Remove tank covers (sect. 5 - 2, Removal of the fuel tank fairings).
Remove hoses (8) and (15) from the filler cap assembly (10).
Open the filler cap.
Unscrew the outer screws (17) securing the ring nut to the filler cap recess.
Remove the filler cap assembly (10).
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Braking
Slow down in time, shift down to engine-brake first and then
brake applying both brakes. Pull the clutch lever before
stopping the motorcycle, to avoid sudden engine stop.
Abs system
Using the brakes correctly under adverse conditions is the
hardest – and yet the most critical - skill to mast ...
Refitting the external components
Fit the cap (39) on spring (38) until it engages.
Mount ball (40), spring (38) with cap (39), washer (37) and screw (36) on the
chain side half-casing by starting the
screw into hole (f).
Note
The spring (38), with cap (39), must be oriented as shown.
Tighten the screw fully home to a torqu ...