Motorcycle Repair: 1971 ironhead sportster, circulation problem, ironhead

Question
QUESTION: the 71 sporty has burned 2 front pistons, within 1000 miles.  The back of the front piston appears to have been melted both times we have had it apart and the wrist pin was froze to the connecting rod bushing.  is it a oil circulation problem ? All the dumbass local harley mech will say is..."its a 71 ironhead".  thanks for you help Mike !

ANSWER: Your oil for the piston comes fromt he bottom end when the flywheels turn and throw oil on the pistons. When install them, what piston to cylinder wall clearence are you using?
Mike

---------- FOLLOW-UP ----------

QUESTION: the mechanic that did the jugs said it was 30 thousands.  (sp?)

Answer
Your piston clearence should be .003-.004, so your ok there.
Make sure the oil drain hole in the cylinder is not plugged.
You might be over heating the cylinder if you are running to lean. Pull the plugs and if they are really white, then you are running lean.
Good luck and happy riding
Mike