All oils have zinc, the package is actually called zddp. It is more expensive to manufacture oils of this type and it kills catalytic converters so automotive oil are capped at a 600 count to extend the converter's life. High zddp packages are needed on flat tappet motors since you have a lot of flat metal on metal fiction with high valve spring pressures, most motorcycle oils are in the 1000 count range since up till recently they where catless.
The highest zddp oil I have found in my research is Belray's EXR oil, it was formulated originally for harley's xr powered flat trackers decades back and is about a 1400 count zddp oil. Not cheap but the best.
The highest zddp oil I have found in my research is Belray's EXR oil, it was formulated originally for harley's xr powered flat trackers decades back and is about a 1400 count zddp oil. Not cheap but the best.