Modern Vespa

I was thinking that if they sold oil and additives separately they could mix at the time of use and so the expiration date would be longer; but the real question continues to be avoided or ignored:
if the liquid is not wine or vinegar in which the longer you have them the more they improve, why buy motor oil if you don't know when you will use it?
And especially if you know it won't get better over time?
(We are truly a consumer society sloth...bleah)

Just buy the quantity you need, when you need it. In the cast of the GTS, you need 1.2L per oil change, so I buy 2L knowing that the left over 0.8L will get used before it has chance to breakdown. Always check the production/use by date on the bottle before you buy it, and resist buying oil marked down in price if you are unsure you are going to use it within a reasonable time.

All very right but ... unintentionally you made me remember that in the car i have something expired for non-use (condom box ) and it was a worse finding than having expired engine oil ...

Do condom's have 'use-by' dates?

All oil manufacturers place either a 4 or 5 year shelf life on their products IF the can or bottle is unopened and it's stored in an ambient temperature. Some very specialised oils have a much shorter life span on the shelf. Exactly how long the 'sealed' shelf life of a particular can of oil is will depend on what oil it is and what it's chemicall make up is.

Once the oil can or bottle is opened it will survive intact for only up to two years after which the oil is on no value as it will not meet the original specifications on the tin and will fail to lubricate properly.
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