Honda CRF450X 2021 Manual page 36

Remember to close the throttle and pull the
clutch lever in completely before shifting.
Learning when to shift gears comes with
experience. Upshift to a higher gear or
reduce throttle before engine rpm (speed)
gets too high.
Downshift to a lower gear before you feel the
engine laboring (lugging) at low rpm.
NOTICE
Downshifting can help slow your motorcycle,
especially on downhills. However, downshifting
when engine rpm is too high can cause engine
damage.
NOTICE
Improper shifting can damage the engine,
transmission, and drive train. Also, coasting or
towing the vehicle for long distances with the
engine off can damage the transmission.
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