5-13
EBU10842
Engine oil
Make sure the engine oil is at the specified level.
Add oil as necessary. (See pages 8-13–8-19.)CAUTION:_ 
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. 
Make sure that no foreign material enters
the crankcase. 
_
Recommended engine oil type and quantity: 
See page 10-2. 
U4XE65.book  Page 13  Tuesday, May 6, 2003  1:38 PM 
10-2
10
Starting system Electric starter and recoil starter
Lubrication system Wet sump
Engine oil:
Type
Recommended engine oil classification: API Service SE, SF, SG type or higher
Quantity:
Without oil filter element removal 1.5 L
With oil filter element removal 1.6 LModel YFM250X
-20˚ -10˚ 0˚
10˚20˚ 30˚40˚50˚C
10W/30
15W/4020W/4020W/50
10W/40
5W/30
CAUTION:
In order to prevent clutch slippage (since the en-
gine 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.
U4XE65.book  Page 2  Tuesday, May 6, 2003  1:38 PM