Yamaha RHINO YXR66FSEW Owner's Manual page 330

NOTE:
_
If a torque wrench is not available when you are in-
stalling the spark plug, a good estimate of the cor-
rect 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.
5. Lower the cargo bed.
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