I just miked them. The upper fork shrouds are 57 mm. That is where the windshield braces mount. I have the Memphis Shades mounts for the Suzuki Maruader 800 on my bike.

--Tom 02 TBA; 130 mains; TBS; Nology Coils&Wires;Unifilter/opened Airbox; -AI/snorkels; -2 baffles;Progressive 440s & Springs