Yamaha BIG BEAR YFM400S Owner's Manual page 157

MODEL
Final gear oil:
Type
Quantity
Periodic oil change
Air filter:
Fuel:
Type
Tank capacity
Reserve amount
Carburetor:
Type/manufacturer
Spark plug:
Type/manufacturer
Gap
Clutch type:
SAE 80 API "GL-4" Hypoid gear oil
0.23 L (0.20 lmp qt, 0.24 US qt)
Dry type element
UNLEADED GASOLINE ONLY
15 L (3.3 Imp gal, 4.0 US gal)
4.0 L (0.9 Imp gal, 1.1 US gal)
BSR33/MIKUNI
DR8EA/NGK
0.6–0.7 mm (0.024–0.028 in)
Wet, centrifugal automatic
10-3
YFM400