Yamaha BIG BEAR PROFESSIONAL 400 YFM400FPT Owner's Manual page 288

CAUTION:
_
Be sure no foreign material enters the final
gear case.
_
7. Install the oil filler bolt, and then tighten it to
the specified torque.
Tightening torque:
Final gear oil filler bolt:
23 Nm (2.3 m·kgf)
8. Check for oil leakage. If oil leakage is found,
check for the cause.
9. Install the final gear case cover bolts, and
then tighten them to the specified torque.
Tightening torque:
Final gear case cover bolt:
23 Nm (2.3 m·kgf)
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