Yamaha Banshee 350 Manuel Du Propriétaire page 266

Recommended oil:
See page 10-2.
Oil quantity:
Periodic oil change:
1.5 L
cC
8 In order to prevent clutch slippage (since
the engine oil also lubricates the clutch),
do not mix any chemical additives. Do not
use oils with a diesel specification of "CD"
or oils of a higher quality than specified. In
addition, do not use oils labeled "ENERGY
CONSERVING II" or higher.
8 Make sure that no foreign material enters
the crankcase.
8-21