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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Stored lap display function
This function displays the stored laps.
To access the function it is necessary to view the ""setting" menu", using
buttons (1) "s" or (2) "t" select the "lap"
function and press the reset button (3) to enter the following page.
Use button (1) "s" or (2) "t" to select "lap data" indication a ...
Reassembly of the crankcase halves
The crankcase halves must be in good condition and perfectly clean. The
mating surfaces must be perfectly flat and free
from burrs.
Overhauling the alternator-side crankcase half
The following parts must be present on the internal side of the crankcase
half:
Gearbox secondary shaft bearin ...