Unless you find out what happened to the oil pressure your new fix may suffer the same failure. Good luck!
Here are some pictures of damage, yes the bike still ran perfectly as seen in the video I first posted. The rattling is the sleeve that came loose and grinding is the intake valve digging into the cylinder head.
Thanks we will look into that since we have the engine open. Thanks for sharing this I am the third owner of the bike so pretty much we going through the whole engine.The clutch pin modification involves grinding 3 flats down the length of the push pin (in the centre of the clutch) to allow more oil into the clutch but I believe it can take pressure off the feed to the top end of the engine.
The modification in well documented on here if you do a search and it might be worth stripping the clutch to see if a previous owner has done the modification.
I use nothing but full synthetic , moto specific oil. Be sure the race oil you choose doesn't need replacing more than usual , some are meant to be changed more frequently than normal and don't have the detergents in them.My only comment would be, remember not oils are equal, I run a fully synthetic race oil, others will have different views, go with what you believe is best but don't go cheap.
I've found when using Silkolene the shifting starts getting notchy faster than a lot of other oils. They all meet the same standards , it's ludicrous to pay more for a name , especially when it's clearly inferior. I won't recommend an oil brand to use , but I will recommend one not to.Silkolene Pro 4 10w40