Not a problem as such, just interested, as I have read that it does and folk have cured noise on triumph engines by replacing, though have not found this personally.
My engine has always been quiet, though I replaced the shaft as very worn, with the oil scrolls nonexistant at the rear underneath and not supplying oil.
Wear in this area of shaft/rickers ,due to the spring tension I assume?. Also replaced some of the rockers with wear on bearing surface with better ones.
After this the rockers could be seen to be supplied with oil.
No difference at all in any engine noise that I could tell, which is what I assumed anyway, as any wear would be taken up and silenced by the spring pressure?
Ta