Yamaha BRUIN YFM25BV Owner's Manual page 294

NOTE:
_
If a torque wrench is not available when you are in-
stalling a spark plug, a good estimate of the correct
torque is 1/4 to 1/2 turn past finger tight. Have the
spark plug tightened to the specified torque as
soon as possible.
_
4. Install the spark plug cap.
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