Thanks, Ian for taking the trouble to reply, but I am seeking info specific to MZs and the Supa5 in particular.
My local bearings trader says C4 mains are Ok for modern Jap motorbikes and would *probably* be OK for an MZ.
The internet has a lot of information about bearings in general, but nothing about what to use in an MZ.
I agree it is wise to follow the manufacturers recommendations, but these have changed for what are essentially very similar engines. Why?
