Then we are back to start, most probable the left hand failure is caused by oilpressure going under a certain (unknown) limit. I would love to have an oilpressure gauge mounted on the bike. (Not the lamp, they tend to lite up when it is either too late or for actuator failing resons. A PSI gauge would be bay far more valuable to me than the ammeter .. (!) Imagine to be able to see what level of pressure you have in a rebuilt A65 and have some kind of log (Like in airplanes) so you could really monitor pressure falling and create some kind of decision point in your mind for renewal before disaster.
I think the hole made to avoid the compression inside the crank shaft so when the oil goes in the crank the release valve will open befor the oil is arrived to the end of crankshaft so the air inside the crank will go out from this hole and then the oil will supply the crank complet befor opening the reaeas valve This is only my opinion may be not true excuse me for my english.
Samhar, Actually your English is not so bad. I understood you quite clearly. I don't think that your opinion of the hole in the rod is as good though. Have a good day! I always enjoy hearing from people in far away places. Are you riding an A65?