Honda 2009 GOLDWING GL1800 Owner's Manual page 171

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.
Engine Oil & Filter
code number of the sales
company of the oil
oil classification
Servicing Your Honda
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