I was shocked to find the rings that came with the pistons for my A10 were way too small and hand about 0.030? gap when tested in the bore! Also, 1 bore I had to hone out 0.003? as it was too tight for the piston (tight spot half down the bore). The replacement set of rings were a bit tight in the bores so I had to file a little off. All-in-all, a lot of fitting needed to be done - so much for having a re-bore and just popping it back together! The advice I got here on the forum was a correct "check it before you fit it" sad but it really saves a load of time. I think I would have missed the piston crown being too thick - that?s a dirty trick!
I once bought new big end nuts and bolts for a commando rebuild and interestingly, the slits in the locking part at the top of the nuts were cut too deep, consequence was that after about 200 miles, the locking ring detached its self from the top of the nut, the nut then form the bolt, the bolt from the big end and bang - totally knackered engine. I was told to sue for compensation HaHa!
PS Do the valves now have sufficient clearance when fully open?
Nigel