On my customers motor, the oil hole above the axle is only in the bore for about the last .125 of lift.
It's pretty far removed from the "source" of the oil, and rotated 90deg from it.

The hole is exposed to the crankcase most of the time.

This really doesn't seem to be a very effective way of oiling the bushing....... And maybe they don't need much oil.
But we have a problem with this motor, and it's going to require a little more investigation to see if we can get to the cause of the problem.