Honda CB300R 2019 Owner's Manual page 138

Emission Control Systems
Evaporative Emission Control System
50 STATE (meets California)
An evaporative emissions control system uses a
canister filled with charcoal to adsorb fuel vapor
from the fuel tank while the engine is off. The
vapor is drawn into the engine and burned
while riding.
Crankcase Emissions Control System
The engine is equipped with a closed crankcase
system to prevent discharging crankcase
emissions into the atmosphere.
Blow-by gas is returned to the combustion
chamber through the front cylinder head, air
cleaner housing and throttle body.
136
Fuel Permeation Emission Control
The fuel tank, fuel hoses, and fuel vapor charge
hoses use fuel permeation control technologies
to prevent fuel vapor emissions. Tampering with
these components to reduce or defeat the
effectiveness of the fuel permeation
technologies is prohibited.