81 GPZ550 fork diameter

New to the forum and bikes in general, so apologies if this has already been answered. What is the fork diameter on the 81 GPZ550? From what I’ve found I think it’s 35mm but I wanted to confirm with the pros

1981 Kz550D1 (Gpz) uses 36mm forks.

Strange but true, the later 1982-83 Kz550H1-H2 (Gpz) uses 35mm. The OD is smaller, but the walls are thicker.

Fork tube chart link for future reference. The 550-D1 isn't listed in the pdf, but from the cross-reference at Partzilla
the 81 GPz 550 has the same fork seals as the 550A/C models. same seals = same diameter.

Ohio Cafe Racers Fork Tube Size Chart pdf

Partzilla >> 1981 KZ550-D1 >> Front Forks
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thanks guys!

Like Martin said, the 81 Gpz has same 36mm fork diameter as the Kz550A (standard) and Kz550C (chain-drive Ltd) models.