Honda CRF450RX 2020 Owner's Manual & Competition Handbook page 66

Fuel System (CRF450R/RWE)
Fuel Pressure Increasing
Make sure enough fuel remains (0.3 US gal (1.0 )
minimum) in the fuel tank and add fuel if
necessary before increasing fuel pressure.
With the throttle closed.
Pull the clutch lever all the way in, and depress the
start button.
The engine will start up with increasing the fuel
pressure.
If the engine does not start, check all connector
connections and/or refer to an official Honda
Service Manual (page 186) for troubleshooting of
the PGM-FI symptom.
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Servicing Your Honda