Spanner nut and bolt sizes explained

Here y go if you can get this sorted it makes it easier to get replacements in stainless

Knowing the spanner or Allen key size along with the length of a bolt will get you all on the Guzzi the only ones not standard as such are the swingarm nuts they are a fine thread.

Ex Smoking Biker has a die to rethread the things if you ever nip it up wrong.