Honda BF40D Owner's Manual page 86

OPERATION
OUTBOARD MOTOR TRIMMED
TOO LOW
When cruising:
(A) Into a high wind, trim the outboard motor down slightly to lower the bow
and improve boat stability.
(B) With a tail wind, trim the outboard motor up slightly to raise the bow and
improve boat stability.
(C) Through rough waves, do not trim the outboard motor too low or too high
to avoid an unstable steering condition.
84
OUTBOARD MOTOR TRIMMED
TOO HIGH
OUTBOARD MOTOR TRIMMED
CORRECTLY