Wave washer, spring washer, 8mm.Used somewhere on most all model Moto Guzzis from 1967 to current production. These wave washers can be substituted in place of metal fold over locking plates on front or rear main bearings and other instances where two aluminum pieces are bolted together. They're also used in multiple other applications including sidestand and crashbar mounts, shift and brake pedal mounts, shock and luggage mounts, as well muffler bracket mounts. Also used on the cylinder stud nuts on many small twin Guzzis.
This washer is an alternative to fold over lock plate part numbers 12012100, 12012800, 12012900, 13058600, 14013000