New Moto Guzzi Door Mats Available Now
Book says 12mm x 1.25 pitch no length
No spacer needed but the bolt goes into a hex nut on the back side of the frame rail.
I was thinking there is a collar or spacer for some reason...
I went to the bike at lunch to eyeball the screw length. My 'poorly calibrated' eyes suggested the screw length is 50mm and there are what appear to be bushings between the crash bar and the frame legs.