The shim over bucket types used on the Z1/KZ900/KZ1000 etc are all 29mm in diameter. The shim under bucket types as used on the 650 and early 4 cylinder 750's are 13mm in diameter. There's no confusing the two types because of the difference in sizes. The 750 twin uses an unique shim all its own and it's 30mm in diameter, IIRC.
The 2 valve Suzukis use a shim over bucket setup but their shims are 29.5mm in diameter....so have your vernier to hand when buying used shims at swap meets so you don't get the wrong shims by accident.
KZ650C2 Stock/mint. Goes by "Ace".
H2A Built from a genuine basket case. Yes,it's a hot rod.
GT550A Stock/mint. Pleasant stroker.
2006 Bandit 1200S for easy LD rapid transit
Various H2 projects in the wings.