Oils that claim to meet both JASO MA and MA2

My 82 KZ305's service manual states to use SE rated automotive oil. But that was 1982 when automotive oils had plenty of zinc. Todays oils have greatly reduced zinc levels, because zinc damages catalytic converters and O2 sensors.
It is my understanding, motorcycle oils rated JASO MA, have enough zinc to protect cams and rockers on older motorcycles.
Motorcycle oils rated JASO MA2 have reduced zinc levels to protect catalytic converters on newer bikes.
Many motorcycle oils are rated both JASO MA and MA2. How can one oil meet both standards?

Overlap in standards? Hard to say without know what exactly those ratings require.

Try searching the internet for "what is JASO MA2". Another search = JASO T 904:2006 clutch system friction test.
From some quick checks MA2 gives improved clutch friction performance & is for use on motorcycles w catalytic converters.
You could check the msds to see how much ZDDP or equivalent is in whatever oil you're considering. For an MA2 oil other anit-wear compounds may be listed.

On an old KZ, especially a 305, I would use Shell Rotella 15W-40 regular in the white bottle or some other heavy duty engine oil marketed for diesel engine use, such as Chevron Delo. These two often times go on sale at various places. The msds should list the amount of ZDDP or equivalent. If you're in a cold climate, then you might need to use a motorcycle specific oil.