50mm ID, 12mm offset (20mm offset incl. sprocket width). Stock style for all 82-85 FXR 5-speed models. The OEM 12mm built-in offset of the FXR sprocket is a good solution to add 6mm additional clearance for 4-speed custom bikes for extra wide rear tires. The FXR type sprocket is otherwise identical to the commonly used FL, FX rear sprockets, which have just 6mm offset.