Honda CRF150F 2007 Owner's Manual page 72

Other viscosities shown in the following chart
may be used when the average temperature in
your riding area is within the indicated range.
JASO T 903 standard
The JASO T 903 standard is an index for
engine oils for 4-stroke motorcycle engines.
There are two classes: MA and MB.
Oil conforming to the standard is labeled on the
oil container. For example, the following label
shows the MA classification.
(1) code number of the sales company of the oil
(2) oil classification
Engine Oil
(1)
(2)
Servicing Your Honda
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