The other day I needed to change my oil for my 1978 Honda cb750k. So I headed to the local Walmart to get some Castrol GTX 20-50w, when taking my quarts of oil I noticed that ist had a new label that stated it was Castrol vintage 20-50w with added zinc for less friction. I ran this grade in the mid 70's on my motorcycles then. A few years most motor oils took the zinc out of the oil. But now I know what oil I will be using in my vintage SOHC Honda cb750. Now I just wish they would bring out Amoco white unleaded gas.
