That’s a good ‘investigation in progress’ Bushman.
It doesn’t seem like you’ve nailed a root cause just yet though. You’ve found lots of ‘points to imrpove’ for sure, but it doesn’t seem like you’ve yet conclusively established the cause of the seizure.
Rocker shafts don’t usually need copious amounts of oil, so whilst I’d fully agree with your analysis that the oiling would be better if it encouraged a small build up of pressure in the shaft, I can’t see that being your root cause. If it was, would all fail in a similar fashion?
Could your oil gallery have been blocked somehow perhaps? But here, your conclusion that the oil ways are over complex and a weakness due to possible blockages is understandable when compared to an old Norton, but in modern engines, there are many long and small galleries, which are not generally seem as a big potential failure mode.
I think you got your ‘sticking some wire in the rockers shaft’ story the wrong way around BTW, my understanding here is that that was done to reduce oil flow to the head in general, as a fix to over full rocker boxes causing oil to be sucked down the guides and burnt.
One question on my mind is your oil choice (I’m gonna start a separate thread on this question BTW). Obviously the cylinder head on and air cooled engine gets bloody hot. Could your oil be breaking down? I’m not sure where you’re at, do you ride in particularly hot climes?
I hope you don’t think I’m nit-picking here or anything like that, im just following your thread with great interest and am keen (as I’m sure you are) to really understand the actual specific root cause of your seized rockers.
