Blumbly, if the smoke was blue it was oil smoke, and indicates a problem. If the engine had been tilted immediately before you ran it, oil could have run into the valve chest, and been sucked into the breather when the engine started. If the engine had been stored upside down or in some other strange position, oil could have slowly run into the cylinder, either past the rings or through the breather. If some nut had been running it on 2 stroke mix, it could have a carboned-up exhaust port and muffler, so you'd get oil smoke until it burned out the crud. However if it had always been the right way up and had not been abused, there's a good chance the bore or piston rings are the problem. Those old 92908s are nice engines but they are plentiful and it is probably not worth rebuilding one that is worn out, unless you enjoy it. You can make a good estimate of the condition of the rings and bore by feeling the compression when you pull the starter, then putting a spoonful of engine oil into the cylinder through the spark plug hole and immediately repeating the test. The oil temporarily seals the compression rings to the cylinder wall: if the compression increases substantially with the oil in the cylinder, the rings are leaking a lot.
