Has an Olympic Basketball (Men) game ever ended 81-25?
Exactly once. On January 1, 1948, Canada beat Iran 81-25, and no Olympic Basketball (Men) game before or since has ended that way. When it happened it was a scorigami, the first 81-25 in league history.
That makes 81-25 the 126th most common final score out of 698 that have ever occurred in Olympic Basketball (Men). One point away, 82-25 has happened never and 81-26 has happened never.