Honda WAVE ALPHA Owner's Manual page 31

Proper shifting can prevent damaging the
engine and transmission.
Upshifting
The upper limit speed of each gear is shown in
gear range.
(P18)
Upshift to a higher gear before exceeding the
upper limit speed.
Upshifting at speeds higher than the upper
limit speed can cause damage to the engine.
Downshifting
Downshifting at speeds higher than those in
the table below may overrev the engine and
can cause damage to the engine and
transmission.
Follow the table below when downshifting the
gears.
Downshifting Acceptable Speed
From 4th to 3rd
From 3rd to 2nd
From 2nd to 1st
75 km/h or less
50 km/h or less
30 km/h or less
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