Hello again
Just an update on the offending stud.
I was unable to get all of the original studs out so sent the upper crankcase(with remaining stud in situ) to engineers.
The original stud broke off on removal and had to be spark eroded out.
Resultant hole was filled,drilled and tapped for new stud BUT drilled 5mm too deep.
Problem not noticed till I tried to fit cylinder head.
Long story short: went back to engineers,process repeated correctly,everything tickety boo,no charge
Thanks for all the input
Foggy
Ian:No,I am not a member.Maybe when bike on road. 2025?