2012 900xp shims OD size

Re: how do you time cams in xp900
I just rebuilt my 900 everything runs great but compression is lower on pto side by 35 lbs. it appears valve shim is to tall and keeping valves open let compression by pass. My question does anyone know the OD of shims. I can’t find stock Oem size printed anywhere I’m thinking 8.9 or 9.48 but can’t verify it anywhere I mic it out at 9.4 just looking for verification so I can order some new shims thanks.