leakdown tests (B.S. ?)

Just wondering just how accurate the leakdown
tests really are. Some people swear by them while others believe that for some reason they are not dependable for air-cooled engines and that decent compression figures are the only guage of the internals. Anybody
out there really have an answer and if it is useless, for what reason ?

Thanks Jerry S

I think that leakdown tests are useful for air cooled engines. However, like any other test, the person conducting it needs to know how to properly interpret the results. They also need to know how to correctly set up the test as well. For example, doing a leakdown test on a stone cold engine will yield frightengly poor results, because the engines internals haven't reached their running tolerances yet.

Just my Cdn$0.02, or whatever that is in Danish Kroner.