Honda 2003 ST1300lA Owner's Manual page 100

Engine Oil
&
API classification
viscosity (weight)
JASO T 903 standard
suggested oil*
* Suggested oils are equal in performance to SJ oils that are not labeled as
energy conserving on the circular API service label.
Your motorcycle does not need oil additives. Use the recommended oil.
Do not use oils with graphite or molybdenum additives. They may adversely
affect clutch operation.
Do not use API SH or higher oils displaying a circular API "energy
conserving" service label on the container. They may affect lubrication and
clutch performance.
NO GOOD
Do not use non-detergent, vegetable, or castor based racing oils.
98
Servicing Your Honda
Filter
SG or higher except oils labeled as energy
on the circular API service label
SAE 1 OW-40
M A
Pro Honda GN4 or HP4 (without
molybdenum additives) 4-stroke oil (USA
&Canada), or Honda 4-stroke oil (Canada
only), or an equivalent motorcycle oil.
OK